Transient distal renal tubular acidosis following hump nosed viper bite: Two cases from Sri Lanka.

Hump-nosed viper (Hypnale hypnale; HNV) is one of the six major snake species in Sri Lanka that cause envenomation. Nephrotoxicity, coagulopathy, and neurotoxicity are wellrecognized features of its envenomation. Type 4 renal tubular acidosis (RTA4) has only once been described previously in this condition, and we report two further cases. Two patients aged 53 and 51 presented following HNV bites with acute kidney injury and microangiopathic hemolytic anemia. Both underwent multiple cycles of hemodialysis until the polyuric phase was reached. Despite polyuria, both patients developed resistant hyperkalemia that needed further hemodialysis. The urinary pH, arterial pH, delta ratio, and transtubular potassium gradient confirmed RTA4. HNV venom has been shown to damage the proximal convoluted tubules in animal studies, but not the distal convoluted tubule, and hence the mechanism of our observation in these two patients is unclear. Unexplained hyperkalemia in recovery phase of HNV bite should raise suspicions of RTA4.

A fatal outcome due to pulmonary hemorrhage following Russell's viper bite.

Russell's viper (RV) envenomation causes local effects, coagulopathy, thrombosis, rhabdomyolysis, acute kidney injury, and neurological manifestations. Although coagulopathy and endothelial destruction causing local and mucosal surface bleeding is known, isolated severe pulmonary hemorrhage is not commonly reported. We report a previously healthy 18-year-old male who had bilateral severe pulmonary hemorrhages, which resulted in a fatal outcome following RV bite. This diagnosis was supported by persistent alveolar shadows, with minimum improvement despite hemodialysis without heparin, mixed acidosis and endotracheal tube bleeding. Other bleeding manifestations were absent. Polyvalent antivenom was administered in lieu of prolonged whole blood clotting time. Thrombocytopenia and mildly deranged clotting parameters were noted. Pulmonary hemorrhages were significant enough to require transfusion. This case highlights the importance of suspecting pulmonary hemorrhages in patients with alveolar shadows and desaturation following RV bite despite the absence of other bleeding manifestations in light of failure of optimum therapy including hemodialysis.

Constrictive pericarditis in a post-renal transplant patient: a case report.

INTRODUCTION: Constrictive pericarditis is a rare complication in the post-renal transplant period. It poses a diagnostic dilemma even in the modern era. Its incidence is not known and tuberculosis is implicated in some of the cases. CASE PRESENTATION: A 54-year-old Sri Lankan man, in the sixth year of transplant presented with resistant ascites, shortness of breath and elevated creatinine from the baseline. Pre-transplant he was empirically treated for tuberculosis pericarditis and was on isoniazid prophylaxis for 1 year following transplantation. Two-dimensional echocardiography and cardiac catheterization confirmed the diagnosis, and pericardiectomy was performed, which resulted in full resolution of the symptoms as well as the graft function. The histology or bacteriology failed to demonstrate features suggestive of tuberculosis in the surgical specimen. CONCLUSION: In constrictive pericarditis, a causative factor is difficult to find. Isoniazid prophylaxis shows benefit in preventing tuberculosis-associated constrictive pericarditis.