Portal vein thrombosis following laparoscopic cholecystectomy complicated by dengue viral infection: a case report

INTRODUCTION: Portal vein thrombosis is an uncommon post-operative complication following abdominal surgery. Although therapeutic anticoagulation is recommended, this treatment may be questionable when the patient has an associated bleeding diathesis. CASE PRESENTATION: We report a case of a 63-year-old woman of Asian Indian ethnicity who developed portal vein thrombosis following an uneventful laparoscopic cholecystectomy for symptomatic gallstones. Her condition was further complicated by dengue viral infection in the post-operative period, with thrombocytopenia immediately preceding the diagnosis of portal vein thrombosis. The etiological connections between dengue viral infection with thrombocytopenia, laparoscopic cholecystectomy, portal vein thrombosis as well as the treatment dilemmas posed in treating a patient with portal vein thrombosis with a bleeding diathesis are discussed. CONCLUSION: When portal vein thrombosis occurs in patients with contraindications to anticoagulation, there is a role for initial conservative management without aggressive anticoagulation therapy and such patients must be approached on an individualized basis.

Ultrasonography of the lower limbs for deep vein thrombosis at the University Hospital of the West Indies

A study was conducted on all patients referred to the ultrasound service of the radiology department of the University Hospital of the West Indies, Kingston, Jamaica, for evaluation of a clinical diagnosis of thrombosis of the deep veins of the lower limb, during the period January 1, 1995, to December 31, 1999. The calf veins were not routinely examined; this study was limited to the popliteal, superficial and deep femoral veins. Two hundred and seventy-four females and 104 males were referred. Seventy females and 32 males had ultrasound findings of deep thrombosis (DVT). The significant findings were that the male: female ratio for confirmed DVT was approximately 1:2; 26 percent of referrals had DVT on ultrasound; DVT was more common on the left and the popliteal vein (48 percent) and the superficial femoral vein (47 percent) accounted for most documented cases of DVT but thrombosis of the profunda femoral vein was unusual accounting for only 5 percent of cases. (AU)

Mesenteric venous thrombosis: a surgical dilemma

The signs and symptoms of mesenteric vascular occlusion or stenosis have been well known and understood and may be of an acute or chronic nature. Mesenteric arterial compromise together with celiac artery stenosis or occlusion accounts for the vast majority of such occurrences. Much less frequently seen is abdominal visceral ischemia or infarction due to mesenteric venous outflow inadequacy. The clinical features of this entity are sometimes initially more vague than the arterial counterpart. Mesenteric venous thrombosis (MVT) may present acutely or chronically and leads eventually to disastrous and often fatal consequences. The specific diagnosis MVT has long been a difficult preoperative surgical dilemma. The aetiology of MVT includes: 1. Congenital haematological aberrations (antithrombin III deficiency, protein C or protein S deficiency) leading to hypercoagulation states 2. Carcinomatosis 3. Intra-abdominal vascular trauma (venous) 4. Intra-abdominal infections, pylephlebitis. A detailed interrogation including a family history is essential where a coagulopathy is suspected. Modern imaging techniques such as magnetic resonance imaging and computed tomography scans are specific in making an accurate and early diagnosis of this entity. Prompt treatment is the sole determinant of a satisfactory outcome. For a long time, surgery often followed by long term anticoagulation was the only available therapeutic modality. More recently, diagnostic imaging followed by thrombolytic therapy offers excellent results and frequently negates the necessity for surgery except where excision of infarcted bowel is manadatory. We report cases of MVT of varying aetiology. Methods of diagnosis, current therapy and outcome are discussed.(AU)

Interethnic variation in genetic risk factors for vascular disease

Genetic predisposition to vascular disease has important implications for population screening and prevention. The most common hereditary cause of venous thrombosis is resistance to activated protein C caused by the G1691A point mutation in exon 10 of the factor V gene (1q21-25) which leads to the substitution of glutamine for arginine (factor V Leiden). A thermolabile variant of 5, 10-methylenetetrahydrofolate reductase (MTHFR) caused by the C677T mutation of the MTHFR gene (1p36.3) which substitutes valine for alanine is associated with the vascular disease risk factor hyperhomocysteinaemia. The possibility that these mutations may predispose individuals of African-American origin to thrombosis was investigated in 9 patients (6 male, 3 female) with sickle cell anaemia who had experienced a thrombotic episode. The frequency of the MTHFR C677T mutation was also determined in unrelated subjects from six different populations: African-Caribbean (50), Oriental (47), Asian Indian (21), Middle Eastern (24), Meditteranean (50) and Northen European (61). The MTHFR and factor gene regions of interest were amplified by the polymerase chain reaction method. Factor V Leiden was screened for by single strand conformation polymorphism analysis and the MTHFR C 677T mutation by Hinf 1 restriction. All patients were homozygous normal (G/G) for the factor V allele. This is consistent with population studies which failed to identify factor V Leiden in normal subjects of Sub-Saharan African populations and found a low frequency (0.65 percent in Black Americans. By contrasts, factor V Leiden was found to be most prevalent in European populations (from 1.4 percent in Finland to 7 percent in Greece). One patient was heterozygous (C/T) and 8 homozygous normal (C/C) for the MTHFR mutation. Population studies revealed the observed frequency of the mutant allele (T) to be lowest in African-Caribbean subjects (9 percent) of whom none were homozygous and only 18 percent heterozygous. The frequency was highest in the Meditteranean population (42 percent), followed by Middle Eastern (38 percent), Northern European (30 percent), Asian Indian (21 percent) and Oriental (19 percent). No deviation from Hardy-Weinberg equilibrium was detected. The proportion of subjects homozygous for the mutation (T/T) was 18 percent Meditteranean, 17 percent Middle East, 10 percent Northern European and Asian Indian and 2 percent Oriental. (AU)