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• PRV commonly presents with migraines but more serious causes of headache must be ruled out. • CT will detect direct signs of cerebral sinus thrombosis in 30% of cases, thus MRI is the investigation of choice. • In polycythaemia hypercoagulable flow abnormalities can generate false positives for CVSTs. • Management consists of acute anticoagulation for the thrombosis and long term venesection and cytoreductive therapy. We report the case of a 59 year old woman who presented with a six week history of worsening bifrontal headache. On CT brain the only abnormal finding was a partially empty sella potentially indicative of increased intracranial pressure. MRI found a large cerebral venous sinus thrombosis in the superior sagittal sinus. Blood tests and a bone marrow biopsy revealed a diagnosis of JAK2 positive primary polycythaemia rubra vera. The lack of sensitivity and specificity of CT in the diagnosis of CVST should engender a low threshold for MRI in patients with risk factors and/or non-diagnostic abnormalities on initial CT. Management of this dual pathology involves both the immediate treatment of the thrombus with heparin bridging to warfarin and the long treatment for polycythaemia involving repeat venesections and cytoreductive therapy. [ABSTRACT FROM AUTHOR]

Hereditary erythrocytosis, thrombocytosis, and neutrophilia are rare inherited syndromes which exhibit Mendelian inheritance. Some patients with primary hereditary erythrocytosis exhibit a mutation in the erythropoietin receptor ( EPOR ) which is associated with low serum erythropoietin (EPO) levels. Secondary congenital erythrocytosis may be characterized by normal or high serum EPO levels, and is related to high oxygen affinity haemoglobin variants, mutation of the enzyme biphosphoglycerate mutase ( BPGM ), or defects in components of the oxygen-sensing pathway. Hereditary thrombocytosis was first linked to mutations in genes encoding thrombopoietin ( THPO ) or the thrombopoietin receptor, MPL . More recently, germline mutations in JAK2 , distinct from JAK2 V617F, and mutation of the gelsolin gene, were uncovered in several pedigrees of hereditary thrombocytosis. Hereditary neutrophilia has been described in one family with an activating germline mutation in CSF3R . The mutational basis for most hereditary myeloproliferative disorders has yet to be identified. [ABSTRACT FROM AUTHOR]

Abstract: Our understanding of the formation of blood cells and its control has evolved over the last 40 years from work originally undertaken in murine and subsequently human marrow cells. This led to the concept of haematopoietic stem cells and more recently these same cells have been shown to be capable of generating other cell types such as liver, pancreas and neural tissue. This topic is huge and the authors have focussed on some of the background and clinical aspects which are of importance to surgeons in training. [Copyright &y& Elsevier]

Abstract: Our understanding of the formation of blood cells and its control has evolved over the last 40 years from work originally undertaken in murine and subsequently human marrow cells. This led to the concept of haematopoietic stem cells and more recently these same cells have been shown to be capable of generating other cell types such as liver, pancreas and neural tissue. This topic is huge and the authors have focussed on some of the background and clinical aspects which are of importance to surgeons in training. [Copyright &y& Elsevier]

Abstract: Disruption of iron homeostasis within the central nervous system (CNS) can lead to profound abnormalities during both development and aging in mammals. The radiation-induced polycythaemia (Pcm) mutation, a 58-bp microdeletion in the promoter region of ferroportin 1 (Fpn1), disrupts transcriptional and post-transcriptional regulation of this pivotal iron transporter. This regulatory mutation induces dynamic alterations in peripheral iron homeostasis such that newborn homozygous Pcm mice exhibit iron deficiency anemia with increased duodenal Fpn1 expression while adult homozygotes display decreased Fpn1 expression and anemia despite organismal iron overload. Herein we report the impact of the Pcm microdeletion on iron homeostasis in two compartments of the central nervous system: brain and retina. At birth, Pcm homozygotes show a marked decrease in brain iron content and reduced levels of Fpn1 expression. Upregulation of transferrin receptor 1 (TfR1) in brain microvasculature appears to mediate the compensatory iron uptake during postnatal development and iron content in Pcm brain is restored to wild-type levels by 7 weeks of age. Similarly, changes in expression are transient and expression of Fpn1 and TfR1 is indistinguishable between Pcm homozygotes and wild-type by 12 weeks of age. Strikingly, the adult Pcm brain is effectively protected from the peripheral iron overload and maintains normal iron content. In contrast to Fpn1 downregulation in perinatal brain, the retina of Pcm homozygotes reveals increased levels of Fpn1 expression. While retinal morphology appears normal at birth and during early postnatal development, adult Pcm mice demonstrate a marked, age-dependent loss of photoreceptors. This phenotype demonstrates the importance of iron homeostasis in retinal health. [Copyright &y& Elsevier]

Abstract: Erythropoietin (EPO) can protect myocardium from ischemic injury, but it also plays an important role in promoting polycythaemia, the potential for thrombo-embolic complications. Local sustained delivery of bioactive agents directly to impaired tissues using biomaterials is an approach to limit systemic toxicity and improve the efficacy of therapies. The present study was performed to investigate whether local intramyocardial injection of EPO with hydrogel could enhance cardioprotective effect without causing polycythaemia after myocardial infarction (MI). To test the hypothesis, phosphate buffered solution (PBS), α-cyclodextrin/MPEG–PCL–MPEG hydrogel, recombined human erythropoietin (rhEPO) in PBS, or rhEPO in hydrogel were injected into the infarcted area immediately after MI in rats. The hydrogel allowed a sustained release of EPO, which inhibited cell apoptosis and increased neovasculature formation, and subsequently reduced infarct size and improved cardiac function compared with other groups. Notably, there was no evidence of polycythaemia from this therapy, with no differences in erythrocyte count and hematocrit compared with the animals received PBS or hydrogel blank injection. In conclusion, intramyocardial delivery of rhEPO with α-cyclodextrin/MPEG–PCL–MPEG hydrogel may lead to cardiac performance improvement after MI without apparent adverse effect. [Copyright &y& Elsevier]

A 6-year-old child with pulmonary arteriovenous malformation (PAVM) of the lower lobe of left lung was successfully treated by left lower lobectomy and the case is reported for its rarity. The exact diagnosis is relatively easy to make by contrast echocardiography and pulmonary angiocardiography, provided the possibility is entertained. Because of recurrent episodes of massive haemoptysis from a single pulmonary lobe, surgical resection was deemed the best curative option to avoid further episodes and recurrence. Published reports detailing coil embolisation therapy for PAVMs are also discussed. [Copyright &y& Elsevier]

Summary: Placental vascular anastomoses are almost invariably present in monochorionic (MC) placentas. These anastomoses are the essential anatomical substrate for the development of several haematological complications in MC twins, in particular twin-to-twin transfusion syndrome (TTTS). Several forms of TTTS have been described, including chronic TTTS, acute perimortem TTTS, twin anaemia–polycythaemia sequence, acute perinatal TTTS and twin reversed arterial perfusion sequence. A significant evolution in prenatal care strategies and management options for patients with TTTS has occurred during the last decade. In chronic TTTS, endoscopic laser ablation of communicating placental vessels has led to an increase in survival rates. This review analyzes the possible pathophysiologic mechanisms involved, discusses the latest findings in diagnosis, therapy and prognosis, and focuses on fetal and neonatal haematologic complications associated with the various forms of TTTS. [Copyright &y& Elsevier]

Abstract: The effects of hypobaric hypoxia in visitors depend not only on the actual elevation but also on the rate of ascent. There are increases in sympathetic activity resulting in increases in systemic vascular resistance, blood pressure and heart rate. Pulmonary vasoconstriction leads to pulmonary hypertension, particularly during exercise. The sympathetic excitation results from hypoxia, partly through chemoreceptor reflexes and partly through altered baroreceptor function. Systemic vasoconstriction may also occur as a reflex response to the high pulmonary arterial pressures. Many communities live permanently at high altitude and most dwellers show excellent adaptation although there are differences between populations in the extent of the ventilatory drive and the erythropoiesis. Despite living all their lives at altitude, some dwellers, particularly Andeans, may develop a maladaptation syndrome known as chronic mountain sickness. The most prominent characteristic of this is excessive polycythaemia, the cause of which has been attributed to peripheral chemoreceptor dysfunction. The hyperviscous blood leads to pulmonary hypertension, symptoms of cerebral hypoperfusion, and eventually right heart failure and death. [Copyright &y& Elsevier]

Summary: Alveolar bone is the least stable of the periodontal tissues, because it is subjected to continuous modeling and remodeling. Objective: To perform a histological and histomorphometric evaluation of bone modeling and remodeling of periodontal alveolar bone under experimental anaemia and polycythaemia. Methods: Thirty Wistar rats were divided into three groups: control (C), animals were i.p. injected with 0.5mL of saline solution; anaemia (A), animals were injected with 6mg/100b.w. of phenylhydrazine every 48h; polycythaemia (P), animals were transfused with 2.5mL/100b.w. of 80% suspension of homologous erythrocytes. All the animals were sacrificed 14 days after the onset of the experiment. The mandibles were resected, fixed in formalin, radiographed, processed and embedded in paraffin. Bucco-lingually oriented sections were obtained at the level of the mesial root of the first lower molar, and stained with hematoxylin-eosin. Histological and histomorphometric studies were performed on the buccal and lingual plates of periodontal alveolar bone. Results: Histological and histomorphometric studies showed a statistically significant decrease in bone formation both in buccal and lingual plates in group A (anaemia) as compared to group C (control). An increase in active bone formation was found in the lingual plate in group P (polycythaemia) as compared to group C (control). Conclusion: The results obtained using this experimental model evidenced alterations in bone modeling and remodeling under conditions of anaemia and polycythaemia and/or associated factors. [Copyright &y& Elsevier]

Abstract: Uterine fibroid or leiomyoma is the commonest benign uterine tumour. Its occurrence in the postmenopausal age group is rare and if enlargement of the fibroid noted during this time, the diagnosis of leiomyosarcoma is provisional until proven otherwise. A case of a postmenopausal woman with a huge uterine fibroid associated with polycythaemia is presented whereby the mass was noted to increase in size within 2 years. The patient was otherwise well except for the growing uterine mass. She had venesection done to treat her polycythaemia and later underwent surgery for total abdominal hysterectomy and bilateral salpingoophoorectomy. The histopathology report confirmed leiomyoma of uterus with no evidence of sarcomatous changes. It was suggested that large uterine myoma may cause secondary polycythaemia by three postulated mechanisms, i.e. presence of hypoxia suggesting shunting within the tumour, second, the uterine fibroid was compressing the ureters resulting in inappropriate excessive production of erythropoietin by the kidneys, and third, the tumour itself may have been producing the erythropoietin. [Copyright &y& Elsevier]

General internists and adult cardiologist are seeing adult congenital heart disease more frequently in their clinical practices. We report the case of a polycythaemic patient with the cerebral and pulmonary arteriovenous malformations (AVMs) who presents with a transient ischaemic attack (TIA). Treatment strategies such as antiplatelet drugs and vensection may at best be ineffective and at worst detrimental to the patient. [Copyright &y& Elsevier]