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Cockroaches serve as mechanical vectors for medically important pathogens, and their presence in hospitals is a common occurrence. This review summarizes the pathogens carried by cockroaches collected in hospitals around the world during the period 2000-2024 and focuses on their antibiotic resistance mechanisms and potential impact on the public health system. The conventional techniques are most used to identify microorganisms and determine antibiotic resistance, but there are few studies that use molecular techniques for bacterial identification and resistance mechanism detection. The species that appear most frequently in the selected articles were Escherichia coli (22 articles) and Pseudomonas aeruginosa (11 articles). Regarding antibiotic resistance, this review describes 79.0% (34/43) of the studies analyzed. E. coli and P. aeruginosa bacteria were found to be resistant to antibiotics in 51.2% and 25.6% of articles, respectively. The identification of pathogens carried by cockroaches collected in hospitals suggests a potential risk of these insects in the transmission of healthcare-associated infections, mainly in developing countries, where this issue is most alarming. The collected data suggest that integrated approaches to cockroach control and infestation management should be put in place based on scientific evidence.

Spirometra (Cestoda: Diphyllobothriidea) affects humans and some species of domestic and wild animals which eventually interact with humans. In this article, we report three new cases of Spirometra decipiens (Diesing, 1850) infection observed in two intermediate hosts and one definitive host, in Cuba. Genetic and morphological identification of S. decipiens in two snakes and a domestic dog were carried out by molecular means and routine histological study using hematoxylin-eosin staining, respectively. Taken together, the anatomical location, the host species infected with the specimens and their morphological and genetic features, all the samples were identified as S. decipiens . In each of the three cases, PCR assays using specific primers amplified bands that corresponded to S. decipiens species. To our knowledge, this paper is the first report of S. decipiens in species of Cuban endemic fauna and in the Caribbean islands. These species constitute a real or potential risk of transmission of Spirometra to humans in Cuba.

Background: Leishmaniasis is a vector-borne disease caused by several species from genus Leishmania. An increase in the number of cases related to human movement has been informed in the last years. Due to the increase of suspicious leishmaniasis cases arriving in Cuba during 2017, a general analysis is presented herein., Methods: Clinical samples were collected from 5 patients suspicious of leishmaniasis, received from January to December 2017 at the Institute of Tropical Medicine Pedro Kourí, Cuba. Skin lesion samples were analyzed using different diagnostic assays: direct smear, histological examination, and molecular analysis for species identification. Epidemiological and demographic data were requested from each case and analyzed. Treatment and follow up of patient was also performed., Results: Five cases were confirmed as Leishmania infection according to microscopic observation and molecular methods results. PCR-18S, PCR-N/RFLP and PCR-F/RFLP identified the following species: L. panamensis (2 cases), L. braziliensis (1 case), L.panamensis/L.guyanensis (1 case), L. mexicana complex (1 case). In treated patients, drugs were well tolerated, cure were documented and no relapse have been currently reported (3 years later)., Conclusions: Clinical characteristics, demographic data, and epidemiological features of infection for each case evidence the potential risk related with travel to endemic areas of leishmaniasis., Keyworks: Cutaneous leishmaniasis, Epidemiology, Imported cases., (© 2022. The Author(s).)

The results of the genotypic characterization of Pneumocystis jirovecii are described in lung tissue samples from 41 Cubans who died of AIDS with pneumocystosis between 1995 and 2008. Histological sections of the lung preserved as formalin-fixed and paraffin-embedded tissue were examined. PCR amplification and nucleotide sequencing of the two mitochondrial genes (large and small) of the pathogen allowed verification of a predominance of genotype 3 (85T/248C) of the large mitochondrial gene and genotype 3 (160A/196T) of the small mitochondrial gene over a period of 14 years (1995-2008). These results suggest that the 85T/248C//160A/196T genotype circulates with the highest frequency (81.3%) among AIDS patients in Cuba. Multilocus analysis indicates a limited circulation of pathogen genotypes on the island with the existence of a clonal genotype with an epidemic structure. Furthermore, it appears that circulating strains of P. jirovecii have not developed mutations related to sulfonamide resistance. Taken together, the data in this study revealed important elements about pneumocystosis in Cuban patients dying of AIDS and the usefulness of formalin-fixed and paraffin-embedded samples to carry out molecular epidemiology studies of P. jirovecii .

Pneumocystis jirovecii and microsporidia species are recognized as opportunistic infectious pathogens in AIDS patients. Coinfection of both in one patient has been rarely reported. The aim of the present study was to investigate the coinfection of P. jirovecii and microsporidia in different tissues from AIDS deceased patients. Post mortem histological finding of P. jirovecii and microsporidia was demonstrated by means of the Grocott's methenamine silver and Brown Brenn staining, respectively. Molecular technique was used for identification and characterization of both fungi. Out of the 514 autopsied cases P. jirovecii and microsporidia species were identified in 53 (10.3%) and 62 (12.1%) cases respectively. A total of five cases (0.97%) coinfected with Pneumocystis and microsporidia were recovered from all analyzed autopsies. Coinfection of Pneumocystis and microsporidia is very challenging and raises interesting issues about host-parasite relationship. The early diagnosis of both pathogens must be crucial to establish correct and early treatments, improve the patient's evolution, reducing the risk of death., (© The Author(s) 2020. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Background: Leishmaniasis is a neglected parasitic disease caused by Leishmania spp., which is not endemic in Cuba. However, several factors (such as human activities, climate changes, and tourism) have led to an increase in the number of leishmaniasis cases in all regions, raising diagnosis and surveillance issues. We aim to present the retrospective analysis of 16 human cases suspicious of leishmaniasis, which were received during 2006-2016 for diagnosis at the Department of Parasitology from the Institute of Tropical Medicine Pedro Kourí, Cuba., Methods: Clinical samples were collected and analyzed via different diagnostic assays, including direct smear, cultivation, histological analysis, and molecular analysis. Epidemiology and background of infection, clinical features, sex and age from each patient was recorded., Results: From the 16 suspicious cases, 5 cases were confirmed for Leishmania infection, based on at least two positive results using different methods: PCR-based diagnosis [18S rRNA (5/5), hsp 20 gene (4/5), hsp 70 gene (3/5)], histopathology evaluation (2/3), parasite cultivation (2/3), or direct smears (2/3). L. braziliensis and L. mexicana were identified as the involving species in two cases, according to hsp 70 PCR-RFLP protocols. Demographic and clinical features, as well as treatment and follow up, are described for every case., Conclusions: The combination of parasitological and molecular methods allowed proper diagnosis of imported leishmaniasis cases in Cuba. The utility and advantages of molecular diagnosis assays in non-endemic countries like Cuba are discussed., Competing Interests: The conditions established by the institutional ethical committee (CEI-IPK) were followed during the diagnostic process. All the rights and expected benefits were explained to each patient in order to obtain their consent for the use of clinical samples with research purposes, as well as the scientific/academic use of their photographs. In case the patients refused to participate, at any moment, they had the right to do it and receive, equally well, proper attention and treatment. The Ethical Committee for Research (CEI- IPK) from the Institute of Tropical Medicine Pedro Kourí, approved the proper use of clinical samples (Dictamen CEI-IPK 1210).Consent for the scientific/academic use of samples and data was obtained from the patients.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Fasciola hepatica is a digenean trematode which infects a wide variety of domestic animals and also humans. Previous studies have demonstrated that four monoclonal antibodies (Mabs) against the total extract of F. hepatica redia (named as 1E4, 6G11, 4E5 and 4G11) also recognized the excretion - secretion antigens (ES Ag) of adult parasites, which is a biologically-relevant mixture of molecules with functional roles during infection and immune evasion on definitive hosts. In the present report we describe the partial characterization of the epitopes recognized by these Mabs by heat treatment, mercaptoethanol reduction, pronase proteolysis and sodium peryodate oxidation, which suggested their predominant protein and conformational nature. Also, a comparative study using immunodetection assays on crude extracts and on histological sections of both rediae and adults of F. hepatica were performed to explore the expression pattern of the antigenic determinants in these developmental stages. From these experiments it was found that the Mabs reacted most likely with the same proteins of approximately 64 and 105 kDa present on both rediae and adult's extracts. However, the 1E4, 6G11 and 4E5 Mabs also recognized other molecules of the total extract of F. hepatica adults, a fact that constitutes an evidence of the antigenic variation between both stages and points at a certain biological relevance of the recognized antigenic determinants. Immunolocalization studies on histological sections revealed that all Mabs reacted with the tegument of F. hepatica in both rediae and adults stages, while the epitopes recognized by 1E4, 6G11 and 4E5 antibodies were also preferentially localized in the intestinal caeca and in different organs of the reproductive system of adult specimens. The immunogenicity of these antigenic determinants, their conserved status among different stages of the life cycle of F. hepatica and their presence in both tegument and ES Ag of adult parasites, are suitable features that suggest their potential use for developing an epitope-based vaccine for fasciolosis control., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: This study aimed to provide information about the molecular epidemiology of human papillomavirus (HPV) in a group of Cuban women., Materials and Methods: DNA from cervical samples was analyzed using a quantitative real-time polymerase chain reaction (PCR), which detects 6 of the clinically most relevant high-risk HPV types. Furthermore, end point PCR and sequencing were performed. Three hundred twenty-two women (211 with positive and 111 with negative cytologic results) aged between 30 and 69 years were enrolled. Risk factors associated with HPV infections and premalignant lesions were also investigated., Results: HPV DNA was detected in 76.1% (245/322) of the studied population, and 34 different genotypes were found. There was an association between HPV infection and low educational level, history of oral contraceptives, menopausal stage, as well as cigarette and/or alcohol consumption. Besides, in a multivariate analysis, previous positive Pap test result and positive colposcopy finding were both predictor variables for HPV infections and for premalignant lesions. Human papillomavirus infection was found in 94.3% of women (199/211) with positive cytologic result and in 41.4% (46/111) of those with negative results, being more likely that the first group was infected with any HPV (odds ratio = 23.43; 95% CI = 11.70-46.92; p = .000). The most common genotypes were HPV types 16, 18, 31, 58, 33, and 45. All the cases with HPV positive findings had at least 1 high-risk HPV genotype., Conclusions: This is the first report of the molecular epidemiology of HPV in Cuban women, based on results from a DNA sequence and quantitative PCR. Most individuals were infected with high-risk HPV types. These findings support the inclusion of HPV vaccine in Cuba.

Polymerase chain reaction (PCR) has made a significant improvement in the diagnosis of toxoplasmic encephalitis (TE). Nevertheless, a wide variety of targets and primers has been used in different assays, and few comparative studies had been carried out. The aim of the present study was to compare the efficiency of 3 conventional PCR methods by using 3 sets of primers targeting the repetitive B1 gene in the diagnosis of TE. Diagnostic sensitivity and specificity of PCR and nested-PCR protocols were assessed for 207 (nested-PCR/T1-T4), 200 (nested-PCR/S1-AS1), and 206 (PCR/B22-B23) cerebrospinal fluid (CSF) samples, including AIDS and HIV-negative patients. The diagnostic sensitivity of PCR and nested-PCR assays was 50.85%, 68.97%, and 72.41% for T1-T4, S1-AS1, and B22-B23, respectively. The diagnostic specificity was high for all the assays showing values between 95% and 97%. In general, the best results were obtained for the B22-B23 set of primers, suggesting their usefulness compared with 2 nested-PCR protocols and showing that this simple and rapid strategy may be the preferred one for the diagnosis of TE in AIDS patients., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Microsporidiosis is a life threatening opportunistic infection of AIDS patients. The infection is usually restricted to specific anatomical areas, but could become systemic depending on the involved species. Genital microsporidiosis in female patients is rare., Objective: To report genital microsporidiosis in female AIDS patients., Methods: Tissues samples from the genital tract (ovary, fallopian tubes and uterus) of eight deceased women who died of wasting syndrome associated to AIDS and disseminated microsporidiosis at the Institute of Tropical Medicine Pedro Kourí were collected between 1997 and 2005. Using an indirect immunohistochemistry assay the microsporidia species involved in those cases were identified., Results: We report several cases of microsporidial infection of the female genital tract. Six out of eight women with the disseminated form of the disease showed the presence of microsporidia in the genital tract. Encephalitozoon cuniculi and Encephalitozoon hellem were identified in the internal lining epithelium of the fallopian tubes and endometrium., Conclusions: Microsporidia species could disseminate to other organs and become systemic in severe immunocompromised cases. To our knowledge this is the greatest number of female genital tract microsporidiosis cases so far reported in humans., (Copyright © 2011 Revista Iberoamericana de Micología. Published by Elsevier España, S.L. All rights reserved.)

Objective: To evaluate the temporal distribution (1991-2009) and associated variation of KSHV subtypes in Cuba., Method: Phylogenetic characterization based on the KSHV K1 gene was performed using 90 KSHV positive samples., Results: Molecular characterization confirmed the prevalence of a wide range of KSHV subtypes (A: n=48 [A5=12]; C: n=15; B: n=22; and E: n=5). In the current study, we observed a significant increase in HHV-8 subtype B after 2004 (p=0.0063). This Subtype B in Cuba was associated with: heterosexual behaviour (OR: 3.63, CI: 1,2-10,98; p=0.03), with the antecedent of acquiring HIV/KSHV in Africa (p=0.0003), with nodular stage of KS lesions (OR 4.2, CI: 1.1 to 15.7; p=0.04)., Conclusion: Our study is the first to report KSHV Subtype B expansion in Cuba, that might be reflective of a change in human behavioural pattern., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The aims of this study were to assess the prevalence of Helicobacter pylori infection and to introduce a new algorithm to improve its diagnosis in Cuban symptomatic children. One hundred and thirty-three consecutive children with upper gastrointestinal symptoms were studied. Patients were endoscoped and antral biopsies were obtained for rapid urease test (RUT), culture and histology. Prevalence of H. pylori infection was 30.8%. No statistical differences were found concerning demographic, socio-economic factors or chief clinical complaints, between H. pylori-positive and negative children, except for haematemesis, which was significantly higher in infected children (p = 0.003). Histologically, there was statistical association between moderate chronic gastritis in infected children (p = 0.04). Culture and RUT had the highest specificity and sensitivity, respectively. The prevalence of H. pylori infection in Cuban symptomatic children is similar to the one observed in developed countries. Culture and RUT is a useful combination to diagnose H. pylori infection in paediatric patients.

Genotypes of two different loci of the Pneumocystis jirovecii mitochondrial gene were studied in specimens from a total of 75 Pneumocystis pneumonia patients in Spain, France and Cuba. A new genotype of the mitochondrial small subunit rRNA gene of P. jirovecii (160A/196T) was identified, which was revealed to be the most common in these three countries, especially in Cuba where its proportion reached 93.8%. Our data imply that the new genotype might be circulating worldwide and also suggests that the distribution of P. jirovecii genotypes could be narrower in islands such as Cuba.

We investigated the frequency of BKV, JCV and SV40 reactivation in three groups of Cuban patients by multiplex nested PCR assay of 40 paraffin-embedded colorectal neoplasm tissues, 113 urine samples, and 125 plasma samples from 27 transplant recipients, and cerebrospinal fluid (CSF) from 67 HIV-1-infected individuals with central nervous system (CNS) disorders. None of these polyomaviruses were detected in colorectal neoplasms. JCV DNA was detected in 2 of 67 patients (2.9%) with CNS disorders, but neither BKV nor SV40 was identified. BKV was found in urine from 38.5% and 28.6% of adult and pediatric transplant recipients, respectively. In adult renal transplant recipients, excretion of BKV in urine was significantly associated with episodes of acute rejection (p=0.012) and with excretion of HCMV in urine (p= 0.008). In Cuba, the polyomaviruses studied here could not be related to colorectal neoplasms, and JCV was rarely detected in CSFs of HIV-1-infected individuals, whilst BKV reactivation was found to occur frequently in organ transplant recipients.

We report a case of an immunocompetent child with simultaneously an infection with Mycobacterium avium and Hodgkin's disease in a cervical lymph node. A positive PCR result for M. avium on a biopsy of the lymph node directed the definitive diagnosis for both etiologies and avoided a possible dissemination of this infection after chemotherapy was started.

In Cuba, previous reports have shown an increase of epidemic KS, reaching a total of 120 cases by the end of 2007, despite the use of HAART. To evaluate and compare the role of human herpes virus 8 (HHV-8) viral loads in different compartments of AIDS-related Kaposi's sarcoma (AIDS-KS) patients real-time polymerase chain reaction (RT-PCR) was used to determine the genome copy number of HHV-8 in plasma, saliva, tissue and peripheral blood mononuclear cells (PBMC) of 49 AIDS-KS patients. Overall, 98% of AIDS-KS patients harbored detectable HHV-8. HHV-8 could be detected in 91.6% of KS tissue lesions showing the highest viral load (median log = 3.14 copies/100 ng DNA) followed by saliva and PBMC which were positive in 78%, and 69.2%; respectively. In contrast, HHV-8 was detected in only 37% of plasma samples, which also showed lower viral loads. Men who had sex with men (MSM) were more likely to have three-times higher HHV-8 genome copies in KS lesions when compared with tissues from heterosexuals individuals (OR 3; 95% CI 1.1 to 12.5). These results emphasize the systemic nature of HHV-8-infection and demonstrate the possible role of saliva in HHV-8 transmission among MSM.

To evaluate the pathogenic mechanisms and transmission routes involved in KSHV infection in 22 Cuban individuals who maintained close contact with epidemic KS patients, real-time PCR was used to quantify KSHV-DNA in clinical samples of plasma, saliva and peripheral blood mononuclear cells (PBMC). KSHV-DNA was detected in 72.7% (16/22) of the contacts. The highest levels of KSHV load were detected in saliva, followed by PBMC (average log copies/100 ng DNA = 1.28 and 1.12), while significantly lower levels were detected in plasma (average log copies/ml = 0.37). Two of three intra-domiciliary and two serodiscordant sexual contacts of AIDS-KS patients were infected with KSHV. The rate of KSHV-DNA detection in saliva and PBMC samples in men who have sex with men (MSM) was significantly higher than in heterosexuals (HT) (p = 0.014). MSM were more likely to harbor KSHV-DNA in saliva when compared with HT individuals (OR 4.33; 95% CI 1.117-16.8). These results emphasize that, in Cuba, KSHV horizontal transmission through saliva may occur, although homosexual behavior may predispose an individual to KSHV acquisition. Even in the absence of disease, KSHV could cause an asymptomatic systemic infection in individuals who maintain close contact with AIDS-KS patients.

Highly active antiretroviral therapy (HAART) has decreased the incidence of opportunistic infections in the central nervous system (CNS) in AIDS patients. However, toxoplasmic encephalitis (TE) still represents the most common cerebral mass lesion in patients infected with human immunodeficiency virus (HIV). The aim of this study was to evaluate nested PCR-B1 using cerebrospinal fluid (CSF) to detect Toxoplasma gondii DNA for the diagnosis of TE. A total of 114 samples were evaluated, and 33/44 samples from patients with TE were positive by PCR (sensitivity 75%), demonstrating the diagnostic usefulness of PCR technique. PCR-B1 products were analyzed by restriction fragment length polymorphism (RFLP) in 30 samples. Only type I allele at B1 was identified in these samples according banding patterns. This is the first report of evaluation of S1-AS1/S2-AS2 set of primers in more than 100 clinical samples as well as the first genotyping study of T. gondii in Cuba.

Background: Toxoplasmic encephalitis (TE) is one of the most common opportunistic infections in immunocompromised patients. In Cuba, despite the highly active antiretroviral therapy, TE is still the most important cause of cerebral mass lesions in patients infected with the human immunodeficiency virus (HIV). The detection of Toxoplasma gondii by PCR may facilitate the diagnosis and follow-up of TE in acquired immunodeficiency syndrome (AIDS) patients by direct identification of parasite DNA in clinical samples. The aim of the present study was to evaluate a rapid PCR method using the B1 gene to detect T. gondii in cerebrospinal fluid (CSF) samples from patients with suspected TE., Methods: CSF samples from AIDS and HIV-negative patients were analyzed. Patients were divided into two groups according to the Centre for Disease Control and Prevention (CDC) criteria for AIDS-related TE: AIDS patients with suspected neurotoxoplasmosis and AIDS and HIV-negative patients with other confirmed neurological diseases but no suspicions of TE. Predictive values, diagnostic accuracy, sensitivity and specificity of the PCR B1 method were calculated., Results: The results obtained from 190 patients showed that this assay has a good sensitivity and specificity (83.3% and 95.7%, respectively) for the diagnosis of TE in AIDS patients., Conclusion: PCR using the B1 gene and B22/B23 set of primers is a single, rapid and reliable method that may be valuable for discrimination between toxoplasmosis and other central nervous system (CNS) diseases.

Background: Among multiple causes of acute myocarditis, viral infection, especially that due to enteroviruses and adenoviruses, is the leading cause. In the summer 2005 an outbreak of a febrile syndrome accompanied by acute cardiac decompensation occurred in infants and young children in Havana City. Eleven patients had a rapid evolution of disease and there were 8 fatalities from cardiac failure secondary to myocarditis., Objective: The aim of the present study was to determine the etiological agent responsible for this outbreak., Study Design: Children admitted to the pediatric hospitals of Havana City from July 3 to August 2 with this clinical presentation were studied. Forty samples of necropsy tissue, cerebrospinal fluid, stools and serum were tested by molecular methods for 14 respiratory viruses, 6 herpesviruses and generic enteroviruses and flavirus and alfaviruses. Viral isolation was performed in A-549 cells. Isolated viruses were typed by sequence analysis., Results: Adenovirus genome was detected in 6 of the 8 fatal cases-the lungs in 5 (63%) and the myocardium in 3 (37%). In two fatal cases, viral genome was detected in both lung and myocardium. Adenovirus was isolated in five fatal cases. In all three non-fatal cases, adenovirus genome was detected and adenovirus was isolated into two. Sequence analysis showed that adenovirus type 5 was the only isolate from fatal cases and adenovirus 1 the only isolate in non-fatal cases. No other viruses were found by PCR or isolation techniques., Conclusion: Adenovirus was the etiologic agent implicated in this myocarditis outbreak and adenovirus type 5 was associated with fatal outcome.

Background: Apoptosis, or programmed cell death, has been implicated in dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) pathogenesis., Objectives: To determine the in vivo apoptosis contribution to the pathogenesis of fatal DHF/DSS during a Cuban dengue epidemic., Study Design: We detected apoptosis by the TdT-mediated dUTP Nick-End Labeling (TUNEL) technique and dengue virus (DENV) antigens by an immunohistochemical assay in different tissues from six individuals who died of DHF/DSS during the Santiago de Cuba DENV-2 epidemic in 1997., Results: DENV antigens were immunolocalized mainly in hepatocytes. Apoptotic cells were found in five of the six cases studied. Apoptosis was demonstrated in liver, brain, intestinal and lung tissues. Severe brain hypoxia and ischemia in the studied subjects during DHF/DSS probably might induce apoptosis in cerebral cells. Apoptotic microvascular endothelial cells (ECs) in pulmonary and intestinal tissues, a finding only previously reported in vitro, are likely related to vascular plasma leakage manifested by the individuals., Conclusions: Apoptosis was demonstrated in cerebral cells, white blood cells, intestinal and pulmonary microvascular ECs from Cuban fatal cases of DHF/DSS. As far as we know, these findings have not been previously reported in DHF/DSS. Our results indicate there is very likely an in vivo contribution of apoptosis to the pathophysiological mechanisms of DHF/DSS.

To investigate the association between human CMV glycoprotein B (gB) genotypes and CMV disease, we retrospectively analysed 73 biological samples from 56 Cuban patients with different CMV-related diseases using a multiplex nested PCR for detection of the reported 5 CMV gB genotypes. All 4 main genotypes 1 to 4 were found in the clinical samples while no genotype 5 was detected. Among the individuals analysed, genotype gB-2 was the most prevalent (38%) followed by gB-1 (30%) and mixed infections (16%) being mainly detected among immunosuppressed patients (7 out of 9), although there was no association between mixed infections and CMV rejection in transplant recipients. Genotype gB-4 was the least frequent (5 patients), which was almost exclusively detected in mixed infections (4 out of 5, p<0.0001). Genotype gB-1 was more frequently detected in AIDS patients (47%) although it was not statistically significant, while 68% of transplant patients showed mixed infections (p<0.05). This study represents the first report of human CMV gB genotypes in Cuban patients; however, the study is limited by the small number patients, thus making it difficult to draw firm conclusions about the distribution of CMV genotypes in Cuba. Nevertheless, this preliminary report has allowed us to identify that the main 4 CMV genotypes are present in the Cuban population, with genotypes 2 and 1 being the most frequent strains.

Most ocular adnexal lymphomas (OAL) are extranodal marginal zone B-cell lymphomas (EMZL) of mucosa-associated lymphoid tissue (MALT)-type. Chronic antigen stimulation has been suggested to have a pathogenetic role in EMZL and Chlamydia psittaci chronic infection has been recently associated with the development of OAL in a series of patients from Italy. To assess this association, an evaluation of the presence of C. psittaci was made in a different OAL population. DNA samples were obtained from formalin-fixed, paraffin-embedded sections samples of 26 patients with OAL, 20 non-OAL and 20 benign ocular lesions, diagnosed and treated between 1998 and 2003 at National Institute of Oncology in Havana, Cuba. All samples were histologically reviewed by an expert pathologist. Fluorescence in situ hybrization (FISH) analysis of translocations involving MALT1 was performed. The presence of bacterial DNA was assessed with a multiplex touchdown enzyme time release polymerase chain reaction. DNA sequencing was performed to confirm suspicious bands. Seventy-three percent of the OAL cases were EMZL and 81% were in stage IE. FISH analysis was performed in 13 OAL cases and none of them evidenced MALT1 translocations. DNA of C. psittaci was detected in 11% of the 46 lymphomas: two orbital EMZL and three non-OAL. All 20 benign ocular lesions were negative for C. psittaci. The low prevalence of C. psittaci in OAL suggests geographical differences in the etiology of this entity. International studies are needed to clarify the role of C. psittaci in OALs.

Two cases with hyperinfection syndrome caused by Strongyloides stercoralis in the development of HIV/AIDS were reported. These patients had a severe immunodepression with lymphocyte counts of the subpopulation of CD4+ T cells under 200 cells/mm3. In the first case, a predominance of respiratory manifestations was observed and numerous Strongyloides rhabditiform larvae were found in sputum and faeces. In the second case, the neurological manifestations were more common, but only a larva of Strongyloides stercoralis could be detected per microscopic field (100X of magnification) in faeces. Both individuals in spite of the applied therapeutics had a fatal end. The importance of this paper is to be aware of the possibility of an infection disseminated by this helminth in some patients, and to be ready for a suitable diagnosis and an adequate treatment or prevention of the fatal consequences of the infection caused by this nematode.

The morphology and histology of the digestive tract of Gambusia puncticulata and Girardinus metallicus fishes used in the biological control of mosquito larvae in Cuba, were described and compared. They were related to the food habits of each species. Gambusia puncticulata has a short and thick intestine, which is characteristic of the carnivorous species, whereas Girardinus metallicus has an elongate and thin spiral rolled up intestine as it corresponds to the omnivorous fishes. It was observed that the histological pattern of the intestine in both species is very simple; however, Gambusia puncticulata presented a great number of ramified microhairiness on comparing it with Girardinus metallicus, which increases this way the digestive yield of its relatively shorter digestive tract.

A 64 years-old patient, who was a farmer suffering from chronic fever for two years, loss of weight and acute asthenia, was studied. He was admitted to "Pedro Kourí" Tropical Medicine Institute where the studies were conducted and revealed a globular sedimentation rate of 116 mm in 2 hours, and anemia of 9,8g% hemoglobin. The laparoscopic study indicated hepatic granulomatosis that was confirmed by hepatic biopsy in which a sample was taken from the liver to be microbiologically and cytologically examined. By microbiological methods, a non-pigmented slowly-growing strain was isolated, which was classified by conventional diagnostic techniques for the non-tuberculous mycobacteria classification and the alternative diagnosing technique known as bidimensional thin layer chromatography to confirm the previous classification and set the mycolic acid patterns. The isolated strain belonged to group III of Rynyon and was identified as Mycobacterium avium-intracellulare.

From April to September 2000, an epidemic of aseptic meningitis spread throughout Cuba, with 16,943 reported cases. Virologic studies identified echovirus 16 as the cause of this epidemic. This is the first reported isolate of echovirus 16 from patients with viral meningitis in Cuba.

The L1 larval stage of Trichinella spiralis induces modification in a portion of striated skeletal muscle cell resulting in the formation of the nurse cell. This specialized host cell is completely encased in a capsule composed mainly of collagen type IV and type VI, which, in turn, is surrounded by a unique rete of vessels whose formation begins on around day 12 after intracellular infection. We investigated the possibility that vascular endothelial growth factor (VEGF) may be up-regulated during nurse cell formation by employing immunohistochemistry and in situ hybridization on synchronously infected mouse muscle tissue. Both VEGF mRNA and VEGF peptide were detected in the developing nurse cell cytoplasm from day 7 up to 16 mo after infection. In addition, VEGF was also detected in cells in the area immediately surrounding the nurse cell on days 15 and 17. On the basis of these results, we propose that hypoxia is induced by T. spiralis within the developing nurse cell some time prior to the up-regulation of VEGF, perhaps as early as day 7. We further propose, on the basis of the continued presence of VEGF in nurse cell cytoplasm, that a constant state of hypoxia cell is maintained.