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Accumulation of lysosomal phospholipids in cells exposed to cationic amphiphilic drugs is characteristic of drug-induced phospholipidosis. The morphological hallmark of phospholipidosis is the appearance of unicentric or multicentric-lamellar bodies when viewed under an electron microscope (EM). The EM method, the gold standard of detecting cellular phospholipidosis, has downsides, namely, low-throughput, high-costs, and unsuitability for screening a large chemical library. This chapter describes a cell-based high-content phospholipidosis assay using the LipidTOX reagent in a high-throughput screening (HTS) platform. This assay has been optimized and validated in HepG2 and HepRG cells, and miniaturized into a 1536-well plate, thus can be used for high-throughput screening (HTS) to identify chemical compounds that induce phospholipidosis., (© 2022. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Phospholipidosis is characterized by the presence of excessive accumulation of phospholipids in different tissue types (lungs, liver, eyes, kidneys etc.) caused by cationic amphiphilic drugs. Electron microscopy analysis has revealed the presence of lamellar inclusion bodies as the hallmark of phospholipidosis. Some phospholipidosis causing compounds can cause tissue specific inflammatory/retrogressive changes. Reliable and accurate in silico methods could facilitate early screening of phospholipidosis inducing compounds which can subsequently speed up the pharmaceutical drug discovery pipelines. In the present work, stacking ensembles are implemented for combining a number of different base learners to develop predictive models (a total of 256 trained machine learning models were tested) for phospholipidosis inducing compounds using a wide range of molecular descriptors (ChemMine, JOELib, Open babel and RDK descriptors) and structural alerts as input features. The best model consisting of stacked ensemble of machine learning algorithms with random forest as the second level learner outperformed other base and ensemble learners. JOELib descriptors along with structural alerts performed better than the other types of descriptor sets. The best ensemble model achieved an overall accuracy of 88.23%, sensitivity of 86.27%, specificity of 90.20%, mcc of 0.765, auc of 0.896 with 88.21 g-means. To assess the robustness and stability of the best ensemble model, it is further evaluated using stratified 10×10 fold cross validation and holdout testing sets (repeated 10 times) achieving 84.83% mean accuracy with 0.708 mean mcc and 88.46% mean accuracy with 0.771 mean mcc respectively. A comparison of different meta classifiers (Generalized linear regression, Gradient boosting machines, Random forest and Deep learning neural networks) in stacking ensemble revealed that random forest is the better choice for combining multiple classification models., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The Quaker parrot has been used as a psittacine model to study clinical lipidology and lipid-related disorders. However, while Quaker parrots appear to be anecdotally susceptible to a variety of spontaneous dyslipidemic disorders and lesions caused by excess lipid accumulation, epidemiologic data are lacking. A multicenter retrospective study on 652 pathology submissions (411 necropsies and 243 biopsies) from Quaker parrots was performed by recording the final pathological diagnoses, age, and sex for each bird. The prevalence of lesions associated with lipid metabolism, such as hepatic lipidosis, atherosclerosis, xanthomas, adipose tumors, coelomic steatitis/steatonecrosis, endogenous lipid pneumonia, and acute pancreatic necrosis/pancreatitis, was reported. Multiple logistic regression models were used to characterize the effects of sex and age on these lesions, and the prevalence of hepatic lipidosis and atherosclerosis was compared to those in a random sample of control psittacine birds. The raw prevalence of atherosclerosis and hepatic lipidosis was 5.6% (95% confidence interval [CI], 3.4%-7.8%) and 21.2% (95% CI, 17.2%-25.1%), respectively. While the prevalence of atherosclerosis was similar to other psittacine species, hepatic lipidosis was more common in Quaker parrots. Quaker parrots also showed a unique susceptibility to acute pancreatic necrosis with a prevalence of 12.9% (95% CI, 9.7%-16.1%). Male parrots were found to be more susceptible than females to lipid accumulation lesions ( P = .0024), including atherosclerosis ( P = .018) and hepatic lipidosis ( P < .001). This retrospective study confirms the high susceptibility of Quaker parrots to lipid-related disorders and presents epidemiological data that may be useful to avian clinicians, pathologists, and researchers using Quaker parrots.

Glomerular lipidosis (GL) is characterized by dilated glomerular capillary loops containing lipid-laden cells (foam cells). Previously, GL was considered to be an incidental finding because affected dogs were typically not azotemic. However, the International Renal Interest Society staging system for canine chronic kidney disease has increased the awareness of other clinical parameters (eg, proteinuria and hypertension) that should be included in the assessment of renal function. As such, the aim of this study was to determine clinical abnormalities and concurrent renal lesions in dogs with GL. GL was identified in renal biopsies from 46 dogs evaluated by the International Veterinary Renal Pathology Service. GL was the sole diagnosis in 5 of 46 cases (11%), all of which were proteinuric. All 5 dogs had at least 1 additional clinicopathologic abnormality consistent with renal disease, including hypertension (4), azotemia (3), and/or hypoalbuminemia (2). The remaining 41 dogs had GL in combination with other glomerular lesions, the most common being focal segmental glomerulosclerosis (16, 35%), lesions consistent with juvenile nephropathy (8, 17%), and glomerular amyloidosis (5, 11%). Overall, dogs with severe GL were younger than were those with mild GL ( P < .001). The percentage of glomeruli affected by GL differed by concurrent diagnoses ( P = .034), with the highest percentage of affected glomeruli in dogs with GL alone or those with concurrent juvenile nephropathy. These findings suggest that GL should be a recognized histologic phenotype of glomerular injury associated with clinical renal dysfunction and/or juvenile nephropathies.

Immunohistochemical staining for the lysosome-associated membrane protein 2 (LAMP-2) has been proposed previously as an alternative to electron microscopy to identify hepatic phospholipidosis. This study used LAMP-2 immunohistochemistry (IHC) to diagnose phospholipidosis in rats exhibiting renal tubular injury. Rats were administered toreforant, a histamine H4 receptor antagonist by oral gavage at a dose of 3, 10, or 100 mg/kg/d for 6 months. Hematoxylin and eosin staining revealed renal tubular epithelial cell vacuolation, hypertrophy, degeneration, and luminal dilation in the 100 mg/kg/d group animals. Renal tubular injury was confirmed using kidney injury marker 1 (KIM-1) IHC. The involvement of phosopholipidosis in the renal injury was investigated by LAMP-2. Adipophilin IHC was included to differentiate phospholipidosis from lipidosis. Increased LAMP-2 staining was observed in the 100 mg/kg/d group animals when compared to vehicle group animals. Lysosome-associated membrane protein-2 staining was most prominent in the outer stripe of the outer medulla where KIM-1 staining was also most prominent. By contrast, adipophilin staining was not increased. Phospholipidosis was also confirmed by electron microscopy. These data support the use of LAMP-2 IHC as a diagnostic tool and suggest an association between phospholipidosis and the renal tubular injury caused by toreforant.

Background: Follicular lipidosis is a rare disease, having only been reported in six Rottweiler dogs. The diagnosis of follicular lipidosis is confirmed by histopathological examination of the affected skin., Objective: To report a case of follicular lipidosis in a dachshund dog., Animals: A 13-month-old female dachshund dog, with hypotrichosis on the head and cervical region from 10 months of age., Methods: Histological examination of skin biopsy specimens., Results: Histological examination revealed basket weave orthokeratosis, ballooning of matrix cells and external root sheath keratinocytes., Clinical Importance: This case report highlights the importance of including follicular lipidosis among the differential diagnoses of noninflammatory and nonhormonal cutaneous lesions in dachshund presented with hair loss., (© 2017 ESVD and ACVD.)

Context: Drug-induced phospholipidosis is one of the significant concerns in drug development, especially in safety assessment and noninvasive diagnostic tool is highly desirable., Objective: The objective of this study is to explored novel biomarkers for phospholipidosis using a metabolomic approach., Method: NMR spectrometry and LC/MS/MS analyses were applied to urine and plasma of rats administrated cationic amphiphilic drugs., Results: The phenylacetylglycine to hippuric acid ratio in plasma was increased in time and dose-dependent manners; and it was well correlated with histopathological observation., Conclusion: The plasma phenylacetylglycine to hippuric acid ratio is a potential marker in monitoring drug-induced phospholipidosis.

Drug-induced phospholipidosis is characterized by intracellular accumulation of phospholipids with lamellar bodies in cells exposed to xenobiotics. Demonstration of the lamellar bodies by transmission electron microscopy (TEM) is the hallmark for a definitive diagnosis of phospholipidosis. However, the preparation of tissue samples for TEM and their ultrastructural evaluation are technically challenging and time consuming. Paraphenylenediamine (PPD) is essentially a fat stain, and the staining mechanism is based upon the osmication of unsaturated lipids. Thus, the application of PPD staining to osmicated tissue samples is considered an optimal way to identify lipids. We evaluated the potential of PPD staining to localize phospholipid accumulations on osmium-fixed semi-thin tissue sections of the lung, kidney, and liver, which were affected with phospholipidosis, under a light microscope. PPD staining revealed the presence of PPD positive dark fine granular material in the cytoplasm for all affected tissues examined, which correlated ultrastructurally with lamellar bodies as well as a light microscopic finding of cytoplasmic vacuolation. The great advantage of PPD is that it can be incorporated into the protocol for standard TEM tissue preparation and significantly improve the efficiency of TEM work. In conclusion, PPD provides a simple, sensitive, and reliable method for visualizing phospholipid accumulation on light microscopy and represents an easy tool to study drug-induced phospholipidosis.

Lipoedema is a chronic progressive adipose disorder that affects mainly women and presents as symmetrical enlargement of the buttocks and legs. It is commonly misdiagnosed as obesity or lymphoedema, but careful assessment will reveal a disproportionate enlargement below the waist which is resistant to dieting, sparing of the feet, legs are tender or painful to touch and bruise easily, there is occasional orthostatic oedema, and there is often significant psychological morbidity. Lipoedema is a oestrogen-regulated condition with onset around puberty in 78% of women, and there is often a strong family history. The condition is exacerbated by weight gain and there is increasing anecdotal evidence that women who are obese are seeking a diagnosis of lipoedema, either to procure NHS funded manual lymphatic drainage, or to medicalise their obesity and avoid acknowledging that the responsibility for their weight gain is lifestyle orientated. Management of lipoedema consists of accurate diagnosis, psychological care, management of orthostatic oedema, and prevention of progression through skin care and weight management.

Although phospholipidosis (PLD) often affects drug development, there is no convenient in vitro or in vivo test system for PLD detection. In this study, we developed an in silico PLD prediction method based on the PLD-inducing mechanism. We focused on phospholipid (PL)-compound complex formation, which inhibits PL degradation by phospholipase. Thus, we used some molecular interactions, such as electrostatic interactions, hydrophobic interactions, and intermolecular forces, between PL and compounds as descriptors. First, we performed descriptor screening for intermolecular force and then developed a new in silico PLD prediction using descriptors related to molecular interactions. Based on the screening, we identified molecular refraction (MR) as a descriptor of intermolecular force. It is known that ClogP and most-basic pKa can be used for PLD prediction. Thereby, we developed an in silico prediction method using ClogP, most-basic pKa, and MR, which were related to hydrophobic interactions, electrostatic interactions, and intermolecular forces. In addition, a resampling method was used to determine the cut-off values for each descriptor. We obtained good results for 77 compounds as follows: sensitivity = 95.8%, specificity = 75.9%, and concordance = 88.3%. Although there is a concern regarding false-negative compounds for pKa calculations, this predictive ability will be adequate for PLD screening. In conclusion, the mechanism-based in silico PLD prediction method provided good prediction ability, and this method will be useful for evaluating the potential of drugs to cause PLD, particularly in the early stage of drug development, because this method only requires knowledge of the chemical structure.

Lipidoses occur for an abnormal storage parenchymal deposition of lipids and products of their metabolism in large amounts or sometimes, involving only some particular tissue structures. The lipid storage is usually due to an inborn error causing an enzyme absence /deficiency in the primary lipidoses and to a complex metabolism alterations in the secondary forms. However, histologically all lipid depositions look very similar, and immunohistochemical investigation, clinical pictures knowledge and genetic tests need to make a correct diagnosis. Lipid deposition causes parenchymal structural changes especially of glomeruli resulting in renal function impairment and proteinuria and haematuria appearance. This manuscript gathers clinical and histological features present in these storage pathologies. Renal involvement is described in Anderson-Fabry disease, in hyperlipoproteinemias, in lecithin-cholesterol acyltransferase deficiency, in Gaucher disease and finally in secondary lipidoses features such as nephrotic syndrome, Alagille disease, and toxic or ischemic renal damage. Recently the replacement enzymatic therapy availability is substantially modifying the clinical picture and the outcome in some lipidoses such as Anderson-Fabry and Gaucher diseases. Therefore, it is import to be aware of these disorders, not only for making a correct diagnosis but also for starting, when it is possible, an effective therapy.

Background: A considerable number of lysosomal storage diseases (LSD), which can occur at any age in life, should be included in the differential diagnosis of histiocytic diseases., Objective: To what extent can pathologists contribute to the diagnostics of LSD?, Material and Methods: In material collected from LSD, morphological storage phenomena in some disease forms, particularly in histiocytic cells from bone marrow smears and some tissues are highlighted, presented and described. Due to the multitude and heterogeneity of LSDs this list is by no means exhaustive., Results: In Gaucher disease, the forms of Niemann-Pick disease, cholesteryl ester storage disease (CESD), GM1 gangliosidosis and other LSDs, the histiocytic storage cells seen, for example, in bone marrow smears can be finely and ultrastructurally differentiated. Thereby, not only the presence of an LSD in general but also some individual types of LSD can be identified, even though preliminarily. To confirm the diagnosis the genetic and sometimes biochemical analysis of blood samples or fibroblast cultures from patients is usually required., Conclusion: The pathologist may be the first to suspect LSD and this applies to LSDs that show storage histiocytes or one of a number of other LSDs in which only minor or absent storage is seen in histiocytes but marked storage phenomena are found in other cell systems. Some of the numerous, extremely heterogeneous LSDs may, however, be overlooked as detailed knowledge of the generally rare LSDs is the domain of LSD specialists. Clinicians, pathologists, geneticists and biochemists should cooperate in solving the diagnostic problems.

Episodic myalgia is a common complaint in children and young adults. While many cases remain idiopathic even after extensive investigation, myalgia can be the first symptom of an underlying serious neuromuscular condition, and can be associated with an increased risk of such serious complications as rhabdomyolysis and malignant hyperthermia. We review and highlight the metabolic myopathies and other increasingly recognised muscle disorders that may present to paediatricians with episodic myalgia or isolated episodes of rhabdomyolysis, and propose a diagnostic algorithm for investigation of these complaints., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Frequently misdiagnosed as obesity, lipoedema is chronic condition involving an abnormal build-up of fat cells in the legs, thighs and buttocks that cannot be shifted by exercise or dieting. Estimated to affect up to 11% of the female population, the condition is widely unknown by health professionals. This means women typically wait for many years before diagnosis. This allows the condition to progress unchecked, resulting in unnecessary deterioration and the development of associated comorbidities, as well as significant pain and mental anguish. A free, 30-minute Royal College of General Practitioners (RCGP) e-learning course created in partnership with Lipoedema UK aims to rectify this situation by educating nurses, GPs and other health professionals on how to diagnose and manage lipoedema in primary care. This article aims to describe the condition of lipoedema, how to recognise/diagnose it, current treatment options and the findings of a 240-patient survey carried out by Lipoedema UK in 2013 that included documenting the difficulties for patients in obtaining a diagnosis as well as the mental and physical effects of the condition.

Drug-induced phospholipidosis (PLD) is a storage disorder of lysosomes characterized by the excessive accumulation of phospholipids as a result of improper medical treatments. Although few evidences have supported that PLD can induce significant pathological consequences, this potential toxicity indeed can put off the drug discovery process. In this research, a high-throughput liposome electrokinetic chromatography (LEKC) method was validated to evaluate the PLD risk of drug candidates by screening drug-phospholipid interaction, which correlates to the phospholipidosis inducing risk. A statistical analysis based on the Spearman's correlation test showed that the retention factors (log k) of the tested drugs in the LEKC system and the literature reported in vivo and in vitro PLD data were highly correlated. In order to investigate the predictability of LEKC, the effect of liposome composition such as the molar ratio of phospholipids and the addition of cholesterol were also discussed in this study. The results indicated that the LEKC method could offer a fast, reliable and cost-effective screening tool for early prediction of the PLD inducing potential of drug candidates., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Kidney biopsies often show accumulation of lipids or lipidlike material. Evidence has been provided that lipids can directly initiate and contribute to the progression of glomerular and tubulointerstitial lesions. In this study we describe a renal lipidosis occurring in patients with a positive history of narcotic abuse who were enrolled in a methadone substitution program. All 3 patients presented with proteinuria (2.5-20 g/d) and impaired renal function. Renal biopsy revealed a pronounced extracellular and intracellular deposition of lipidlike material in the glomerular, interstitial, and tubular compartments. Known causes of lipid storage could be excluded clinically and morphologically. We consider this to be a distinct renal lipidosis associated with narcotic abuse, methadone intake, or intravenous abuse thereof.

Drug-induced phospholipidosis is characterized by the accumulation of intracellular phospholipids in cells exposed to cationic amphiphilic drugs. The appearance of unicentric or multicentric multilamellar bodies viewed under an electron microscope (EM) is the morphological hallmark of phospholipidosis. Although the EM method is the gold standard for detecting cellular phospholipidosis, this method has its drawbacks, including low throughput, high cost, and unsuitability for screening a large chemical library. In this study, a cell-based phospholipidosis assay has been developed using the LipidTOX Red reagent in HepG2 cells and miniaturized into a 1536-well plate format. To validate this assay for high-throughput screening (HTS), the LOPAC library of 1280 compounds was screened using a quantitative HTS platform. A group of known phospholipidosis inducers, such as amiodarone, propranolol, chlorpromazine, desipramine, promazine, clomipramine, and amitriptyline, was identified by the screen, consistent with previous reports. Several novel phospholipidosis inducers, including NAN-190, ebastine, GR127935, and cis-(Z)-flupentixol, were identified in this study and confirmed using the EM method. These results demonstrate that this assay can be used to evaluate and profile large numbers of chemicals for drug-induced phospholipidosis.

A 30 year old lady patient of SLE on steroid and hydroxychloroquine therapy presented with lupus nephritis and later developed cardiac symptoms. Her renal biopsy revealed features of Class III lupus nephritis. Also seen was typical lamellated myelinoid material in the glomerulus. The alpha-galactosidase A activity was normal. The clinical morphological and biochemical findings were consistent with Lupus nephritis showing changes of hydroxychloroquine induced phopholipidosis. Electron microscopy along with careful clinical examination and follow up status was instrumental in the diagnosis of the latter.

Drug-induced phospholipidosis (PLD) is an excessive accumulation of polar phospholipids within cells as a result of medical treatment. Even though a direct link between in vitro drug-induced PLD and toxicity in humans has not yet been firmly established, the development of PLD during preclinical testing in animals is a recognized problem in the pharmaceutical industry and can delay or abort the development process. Therefore, it is of interest to investigate the potential PLD risk of candidates at an early stage of the drug discovery process. In this work, a high throughput physicochemical approach, which is based on measuring the retention factors of the test compound within several different separation systems, was developed for screening phospholipidosis-inducing potential (PLIP) of pharmaceuticals. The measured retention factors of 36 drugs were compared with literature data on PLIP risk from three different sources. It is clearly shown that there is a statistical correlation between the chromatographic retention parameters of tested drugs and their PLIP risk. In conclusion, the retention factor (logk(AOT)) observed on a docusate sodium salt (AOT) surfactant vesicle electrokinetic chromatography (EKC) system and the logarithm of the volume of distribution (logV(d)) calculated from immobilized artificial membrane chromatography at pH 7.4 (CHI IAM(7.4)) and HSA binding value (% HSA) can provide primary profile prediction for a large number of drug candidates early in the drug discovery process with minimal resources. The observations are that the higher the value of both logk(AOT) and logV(d), the higher the PLIP risk, and we would recommend this dual approach., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Phospholipidosis (PLD) is a topic of concern in drug development because it may be associated with toxicological consequences. The aim of the study was to determine the best method to screen proprietary compounds with regard to their potential to induce PLD. Two in vitro approaches, a genomic method previously evaluated in our laboratory and a fluorescent cell based approach to detect PLD were compared using HepG2 cells. The same set of reference compounds (15 PLD inducing, 7 non-PLD inducing and 4 additional compounds) were used to compare both approaches. The same sensitivity (15/15) and similar specificity (7/7 versus, 6/7 for the genomic approach) were obtained. In addition, 11 proprietary compounds were tested in 4-day exploratory rat toxicity studies as well as in both in vitro approaches. Two of the 11 compounds induced alveolar foamy macrophages and lung vacuolization in vivo and were considered as PLD inducers. Sensitivity (2/2) and specificity (7/9) were better with the fluorescent method than with the genomic approach (1/2 and 3/9, respectively). In conclusion, compared to the genomic approach, the fluorescent method is the test of choice for screening compounds at an early stage of drug development. Indeed, the fluorescent method is more adapted to medium throughput, detects the positive reference compounds at lower (8/15) or equal (7/15) concentrations, allows multiplexing and is associated with higher sensitivity and specificity to predict lung foamy macrophages and vacuolization in vivo. Nevertheless, to confirm our conclusion, it would be necessary to compare the predictivity of both in vitro approaches by using a wide range of reference and proprietary compounds, with information on their potential to induce PLD under in vivo conditions., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Blood indicators are used as a tool to diagnose metabolic disorders. The present work was conducted to study the relationships among blood indicators of lipomobilization and hepatic function in high-yielding dairy cows. Two groups of Holstein cows were studied: 27 early lactation cows and 14 mid lactation cows from four different herds with similar husbandry characteristics in Galicia, Spain. Blood samples were obtained to measure beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), triglycerides (TG), and the activity of aspartate transaminase (AST) and gamma-glutamyl transferase. Cows in early lactation had higher levels of BHB and NEFA than mid lactation cows. High lipomobilization (NEFA > 400 µmol/L) was detected in 67% and 7% of early lactation and mid lactation cows, respectively, while subclinical ketosis (BHB > 1.2 mmol/L) was detected in 41% and 28% of the early lactation and lactation cows, respectively. TG concentrations were low in all cows suffering subclinical ketosis and in 61% of the cows with high lipomobilization. During early lactation, 30% of cows suffered hepatic lipidosis as detected by levels of AST. Compromised hepatic function was observed in early lactation cows as shown by lower concentrations of glucose, total protein, and urea.

Refeeding syndrome is characterized by severe hypophosphatemia occurring in patients given enteral or parenteral nutrition after severe weight loss. There are few veterinary reports that describe this syndrome but it is well documented in human medicine. This report describes a case of a domestic shorthair cat diagnosed with hepatic lipidosis following a 4-week history of decreased appetite and weight loss and in whom refeeding syndrome was documented after initiation of enteral nutrition. Clinical findings, blood work abnormalities and disease progression in this patient are described from the time of diagnosis through to recovery. A review of the current literature pertinent to this clinical syndrome is included., (Copyright © 2011 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.)

Gallbladder cholesterosis (GBC) was described more than 150 years ago, but so far the disease remains unknown. With respect to children's age appear solitary works. The introduction of modern pediatric practice of the intrascopic research methods enabled us to objectively identify the pathological changes in the gallbladder wall. Many years of experience studying gallstone disease has shown that almost a third of children cholelithiasis combined with gallbladder cholesterosis. However, until cholecystectomy the last one was diagnosed in only 10% of children. Meanwhile, our experience in children observing with GBC showed that conservative therapy effective in childhood. The aim of this study was to demonstrate the clinical example of the possibility of conservative treatment of gallbladder cholesterosis in children.

Drug-induced phospholipidosis is a side effect for which drug candidates can be screened in the drug discovery phase. The numerous in silico models that have been developed as a first line of screening are based on the characteristic physicochemical properties of phospholipidosis-inducing drugs, e.g. high logP and pK(b) values. However, applying these models on a predominantly high lipophilic, basic CNS chemistry results in a high false positive rate and consequently in a wrong classification of a large number of valuable drug candidates. Here, we tested 33 CNS-compounds (24 in vivo negative and 9 in vivo positive phospholipidosis-inducers) in our in house developed in vitro phospholipidosis screening assay (Mesens et al., 2009) and compared its predictivity with the outcome of three different, well established in silico prediction models. Our in vitro assay demonstrates an increased specificity of 79% over the in silico models (29%). Moreover, by considering the proposed plasma concentration at the efficacious dose we can show a clear correlation between the in vitro and in vivo occurrence of phospholipidosis, improving the specificity of prediction to 96%. Through its high predictive value, the in vitro low throughput assay is thus preferred above high throughput in silico assays, characterized by a high false positive rate., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

Importance to the Field: Drug-induced phospholipidosis (PL) is a phospholipid storage disorder characterized by the accumulation of multi-lamellar bodies (myeloid bodies) in tissues. A major unanswered question is whether PL represents a benign adaptive response, symptom or early event in drug toxicity. The absence of a non-invasive biomarker to monitor tissue PL has made it difficult to determine the prevalence and implications of PL in the clinic. As a result, the interpretation of PL in risk assessment remains uncertain in preclinical and clinical drug development., Areas Covered in This Review: This review describes the rationale for bis(monoacylglycerol)phosphate (BMP) as a biomarker of PL and explores the potential links between PL and the toxicities of drugs., What the Reader Will Gain: The similarities between the hypothesized roles of BMP in PL and Niemann-Pick type C disease are discussed. The potential implications of PL for cellular function are described in the context of drug-induced QT prolongation, myopathy and renal toxicity., Take Home Message: A specific species of BMP, di-docosahexaenoyl-BMP, should be investigated further as a non-invasive biomarker to monitor the onset and time course of PL and to better understand the functional consequences which could contribute to the toxicities of drugs.

Lipoedema is a distinct clinical condition characterized by bilateral, symmetrical enlargement of the buttocks and lower limbs owing to excess deposition of subcutaneous fat. It is found almost exclusively in women. The common features associated with this condition are 'column- shaped' legs with sparing of the feet, bruising, sensitivity to pressure, and orthostatic oedema. The progression to lipo-lymphoedema or morbid obesity is possible. Conservative measures used in the management of lymphoedema can prevent progression/limit the orthostatic oedema. Surgical procedures may also play a part in the management of lipoedema.

X-linked genetic diseases include a wide range of disorders such as the dystrophinopathies. Additionally in some rare genetic diseases, severity of expression is gender dependent. Prevention of such disorders usually involves prenatal diagnosis and termination of affected pregnancies, while preimplantation genetic diagnosis (PGD) represents a specialized alternative that avoids pregnancy termination. To preclude the rejection of unaffected male embryos that cannot be differentiated from those affected when using fluorescence in-situ hybridization, a flexible protocol based on multiplex fluorescence polymerase chain reaction (PCR) was standardized and validated for gender determination in single cells, which can potentially incorporate any disease-specific locus. The final panel of nine loci included four loci on the Y chromosome, two on the X chromosome plus up to three microsatellite markers to either support the gender diagnosis or to further monitor extraneous contamination. The protocol, standardized on single lymphocytes, established a PCR efficiency of >93% for all loci with maximum allele dropout rates of 4%. Microsatellite analysis excluded external contamination and confirmed biallelic inheritance. Proof of principle for the simplicity and flexibility of the assay was demonstrated through its application to clinical PGD cycles for lipoid congenital adrenal hyperplasia, which presents a more severe clinical course in males, and Duchenne muscular dystrophy.

Chanarin-Dorfman disease (CDD) is a rare genetic disorder characterized by ichthyosis, myopathy, central nervous system disturbances, and intracellular lipid storage in muscle fibers, hepatocytes, and granulocytes. We describe skeletal muscle magnetic resonance imaging findings in a case of CDD, outlining the potential role of GE T1-weighted opposed-phase sequence (chemical shift imaging) in the evaluation of lipid storage myopathies.

We describe the clinical features, muscle pathology features, and molecular studies of seven patients with Chanarin-Dorfman syndrome (CDS) or neutral lipid storage disease and ichthyosis (NLSDI), a multisystem triglyceride storage disease with massive accumulation of lipid droplets in muscle fibers. All patients presented with congenital ichthyosiform erythroderma, cytoplasmic lipid droplets in blood cells, mild to severe hepatomegaly, and increased serum CK levels and liver enzymes. Three patients showed muscle symptoms and three had steathorrea. Molecular analysis identified five mutations, three of which are novel. These findings expand the clinical and mutational spectrum and underline the genetic heterogeneity of this disease.

Dorfman-Chanarin syndrome is a rare, autosomal recessive inherited lipid storage disease with congenital ichthyotic erythroderma due to an acylglycerol recycling defect. It is characterized by accumulation of neutral lipids in different tissues. Liver, muscle, ear, eye, and central nervous system are generally involved, so we presented a patient with severe ichthyosis, lipid vacuoles in neutrophils, and multiorgan involvement including a very rare complication, renal involvement. A 7-month-old girl was presented with frequent respiratory infection, congenital ichthyotic erithroderma and suspicion for immune deficiency. On her physical examination hepatomegaly, developmental delay, palmar and plantar hyperkeratosis and increased deep tendon reflexes with clonus and high tonus were found. Laboratory investigations revealed elevation at transaminases levels, hypoalbuminemia, hypergammaglobulinemia, presence of autoantibodies and eosinophilia. Vacuolization in leukocytes confirmed Dorfman-Chanarin syndrome, whereas no mutation at RAG1-2 and ARTEMIS genes ruled-out immune deficient status of the patient. At the age of eight months the patient died from severe renal failure. Her necropsies demonstrated microvesicular lipid accumulation not only at the liver but also at the renal species. The variability of involvement of different systems in Dorfman-Chanarin syndrome is well described, however the renal findings has not been reported previously at the literature.

A review is presented of the major clinical features of a number of glycolipidoses including Fabry, Gaucher, Tay-Sachs, metachromatic leukodystrophy as well as CeroidLipofucinosis and Sjogren-Larsson syndrome. The possibilities offered by lipidomics for diagnosis and follow-up after enzyme replacement therapy are presented from a practical perspective. The contribution of HPLC coupled with tandem mass spectrometry has considerably simplified the detection and assay of abnormal metabolites. Corresponding internal standards consisting of weighed mixtures of the stable-isotope labeled metabolites required to calibrate and quantitate lipid components of these orphan diseases standards have yet to become commercially available. A lipidomics approach has been found to compare favorably with DNA-sequence analysis for the rapid diagnosis of pre-birth syndromes resulting from these multiple gene defects. The method also seems to be suitable for screening applications in terms of a high throughput combined with a low rate of false diagnoses based on the wide differences in metabolite concentrations found in affected patients as compared with normal subjects. The practical advantages of handling samples for lipidomic diagnoses as compared to enzyme assay are presented for application to diagnosis during pregnancy.

Hepatocellular vacuolation can be a diagnostic challenge since cytoplasmic accumulations of various substances (lipid, water, phospholipids, glycogen, and plasma) can have a similar morphology. Cytoplasmic accumulation of phospholipids following administration of cationic amphiphilic drugs (CAD) can be particularly difficult to differentiate from nonphosphorylated lipid accumulations at the light microscopic level. Histochemical methods (Sudan Black, Oil Red-O, Nile Blue, etc.) can be used to identify both nonphosphorylated and/or phosphorylated lipid accumulations, but these techniques require non-paraffin-embedded tissue and are only moderately sensitive. Thus, electron microscopy is often utilized to achieve a definitive diagnosis based upon the characteristic morphologic features of phospholipid accumulations; however, this is a low throughput and labor intense procedure. In this report, we describe the use of immunohistochemical staining for LAMP-2 (a lysosome-associated protein) and adipophilin (a protein that forms the membrane around non-lysosomal lipid droplets) to differentiate phospholipidosis and lipidosis, respectively in the livers of rats. This staining procedure can be performed on formalin-fixed paraffin embedded tissues, is more sensitive than histochemistry, and easier to perform than ultrastructural evaluation.

Lipohypertrophy has been a recognized complication of insulin therapy for many years, yet research shows that its prevalence in insulin-injecting patients with diabetes remains high. The problem for the patient is that the injection of insulin into a site of lipohypertrophy, although painless, may lead to erratic absorption of the insulin, with the potential for poor glycaemic control and unpredictable hypoglycaemia. Despite the important implications of this for diabetes control in insulin-injecting patients, there is a dearth of information and completed research into the condition. This article raises awareness of lipohypertrophy by reviewing the available literature on the prevention, identification and management of the condition from a nursing perspective. Recommendations for medical and nursing practice in diabetes care to improve prevention and management of lipohypertrophy are made.

This article focuses on neoplastic diseases because they may be the most frequent disease processes in captive hedgehogs according to the literature and authors' case files and the most common cases submitted for cytologic diagnosis in these species, particularly the African hedgehog (Atelerix albiventris).

Phospholipidosis, or intracellular accumulation of phospholipids, is caused by specific classes of xenobiotics. This phenomenon represents a challenge for risk assessment that could benefit from the use of biomarkers in the clinical development of new drug candidates. Flow cytometry, coupled with the lipophilic fluoroprobe Nile red, was correlated to histopathology, electron microscopy and inorganic phosphorus detection to validate the utility of this method for monitoring phospholipidosis in peripheral blood leukocytes. Replicate studies with model test compounds were conducted in which F344 rats were given 4 or 7 doses of either maprotiline hydrochloride, imipramine hydrochloride, tilorone dihydrochloride, amikacin hydrate or vehicle control. Transmission electron and light microscopy were used to examine peripheral blood smears and tissue samples for the presence of cytoplasmic vacuoles. Unstained and Nile red stained lysed peripheral blood samples were acquired for analysis using a FACScan flow cytometer. Inorganic phosphorus concentration in the liver was determined from extracted phospholipids and compared with flow cytometry and histological data. It was demonstrated that flow cytometric analysis of Nile red stained lysed whole blood can be used to detect drug-induced phospholipid accumulation in circulating peripheral leukocytes. Furthermore, clinically detectable leukocyte phospholipidosis may be a useful surrogate for coincident or premonitory detection of target organ phospholipidosis., (Copyright 2005 John Wiley & Sons, Ltd.)

The usefulness of computed tomography (CT) for the diagnosis of feline hepatic lipidosis (FHL) was evaluated. Liver CT number was 54.7+/-5.6 HU (mean+/-SD) in 26 healthy cats. We fast 6 healthy cats for 72 hr to induced FHL experimentally and the cats were assessed by CT and serum biochemical analysis. Liver CT number of the six cats was 53.8+/-3.0 HU before fasting, 46.8+/-2.4 HU after fasting, and 50.2+/-3.6 HU two weeks after restarted feeding. The decreased CT number was associated with the elevation of serum non-esterified fatty acid (NEFA) and beta-hydroxybutyrate levels. These results indicate that measurement of CT number of the liver is an effective procedure for the diagnosis of FHL.

Rare diffuse infiltrative lung diseases are a challenge for clinicians, radiologists, and pathologists for at least three reasons: (a) their low incidence and prevalence hamper the acquisition of expertise and frequently the diagnosis is delayed; (b) therapeutic actions are mainly empirical and based on steroid use, and (c) pathogenetic events are difficult to explain and only recently new therapeutic measures taking advantage of innovative genetic and/or immunopathogenetic studies have been suggested. In this review rare diffuse lung disorders are briefly discussed (pulmonary alveolar proteinosis, inherited lipidoses, acute eosinophilic pneumonia, amyloidosis, pulmonary ossification, pulmonary alveolar microlithiasis). The list is obviously not exhaustive and arbitrarily chosen. The intent is, however, to emphasize that in this difficult field multidisciplinary expertise and the knowledge of the most recent pathogenetic mechanisms have the main role in diagnosis and treatment.

A sheep flock experienced losses in weaned lambs from myopathy and hepatic lipidosis. Investigation revealed painful ambulation, illthrift, and unexpected death in lambs with normal selenium levels, deficient vitamin E levels, and elevated muscle and liver enzyme levels. Vitamin E deficiency should be considered when investigating myopathy and illthrift in lambs.

The use of digital fluorescein corneal angiography to assist argon laser photocoagulation is reported. Photocoagulation was performed on the vascular supply of lipid keratopathy in the left eye of a 44-year-old woman.