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.

Baseline Polymorphisms and Emergence of Drug Resistance in the NS3/4A Protease of Hepatitis C Virus Genotype 1 following Treatment with Faldaprevir and Pegylated Interferon Alpha 2a/Ribavirin in Phase 2 and Phase 3 Studies.

Analysis of data pooled from multiple phase 2 (SILEN-C1 to 3) and phase 3 studies (STARTVerso1 to 4) of the hepatitis C virus (HCV) nonstructural protein 3/4A (NS3/4A) protease inhibitor faldaprevir plus pegylated interferon alpha/ribavirin (PR) provides a comprehensive evaluation of baseline and treatment-emergent NS3/4A amino acid variants among HCV genotype-1 (GT-1)-infected patients. Pooled analyses of GT-1a and GT-1b NS3 population-based pretreatment sequences (n = 3,124) showed that faldaprevir resistance-associated variants (RAVs) at NS3 R155 and D168 were rare (<1%). No single, noncanonical NS3 protease or NS4A cofactor baseline polymorphism was associated with a reduced sustained virologic response (SVR) to faldaprevir plus PR, including Q80K. The GT-1b NS3 helicase polymorphism T344I was associated with reduced SVR to faldaprevir plus PR (P < 0.0001) but was not faldaprevir specific, as reduced SVR was also observed with placebo plus PR. Among patients who did not achieve SVR and had available NS3 population sequences (n = 507 GT-1a; n = 349 GT-1b), 94% of GT-1a and 83% of GT-1b encoded faldaprevir treatment-emergent RAVs. The predominant GT-1a RAV was R155K (88%), whereas GT-1b encoded D168 substitutions (78%) in which D168V was predominant (67%). The novel GT-1b NS3 S61L substitution emerged in 7% of virologic failures as a covariant with D168V, most often among the faldaprevir breakthroughs; S61L in combination with D168V had a minimal impact on faldaprevir susceptibility compared with that for D168V alone (1.5-fold difference in vitro). The median time to loss of D168 RAVs among GT-1b-infected patients who did not have a sustained virologic response at 12 weeks posttreatment (non-SVR12) after virologic failure was 5 months, which was shorter than the 14 months for R155 RAVs among GT-1a-infected non-SVR12 patients, suggesting that D168V is less fit than R155K in the absence of faldaprevir selective pressure.

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.

Corneal perforation due to Acinetobacter junii: a case report.

Acinetobacter spp. is emerging as a common cause of nosocomial infections. Community acquired ocular infections due to Acinetobacter are rare. Only one case of perforation of cornea has been reported previously, where old nomenclature was used to describe the causal agent. We report a case of corneal perforation due to Acinetobacter junii for which a therapeutic penetrating keratoplasty was conducted and the patient eventually recovered.