Bilateral acute renal cortical necrosis after a dog bite: case report.

BACKGROUND: Capnocytophaga canimorsus is a Gram-negative capnophilic rod and part of dogs/cats' normal oral flora. It can be transmitted by bites, scratches, or even by contact of saliva with injured skin. Asplenic patients and patients with alcohol abuse are at particular risk for fulminant C. canimorsus sepsis. However, also immunocompetent patients can have a severe or even fatal infection. This is the first case of a severe C. canimorsus infection in an immunocompromised host complicated by acute renal cortical necrosis with a "reverse rim sign" in contrast-enhanced computed tomography on hospital admission. CASE PRESENTATION: We report the case of a 44-year functionally asplenic patient after an allogeneic stem cell transplantation, who presented with septic shock after a minor dog bite injury 4 days prior. Because of abdominal complaints, epigastric pain with local peritonism, and radiological gallbladder wall thickening, an abdominal focus was suspected after the initial work-up. The patient underwent emergent open cholecystectomy, but the clinical suspicion of abdominal infection was not confirmed. Septic shock was further complicated by cardiomyopathy and disseminated intravascular coagulation. As a causative pathogen, C. canimorsus could be isolated. The clinical course was complicated by permanent hemodialysis and extensive acral necrosis requiring amputation of several fingers and both thighs. CONCLUSION: We present a severe case of a C. canimorsus infection in a functionally asplenic patient after a minor dog bite. The clinical course was complicated by septic shock, disseminated intravascular coagulation, and the need for multiple amputations. In addition, the rare form of acute renal failure - bilateral acute renal cortical necrosis - was visible as "reverse rim sign" on computed tomography scan. This case is an example of the potential disastrous consequences when omitting pre-emptive antibiotic therapy in wounds inflicted by cats and dogs, particularly in asplenic patients.

Probiotic Lactobacillus reuteri ameliorates disease due to enterohemorrhagic Escherichia coli in germfree mice.

Strains of enterohemorrhagic Escherichia coli (EHEC) are a group of Shiga toxin-producing food-borne pathogens that cause severe hemorrhagic colitis and can lead to hemolytic-uremic syndrome (HUS), a life-threatening condition that principally affects children and for which there is no effective treatment. We used a germfree mouse model of renal and enteric disease due to EHEC to determine if probiotic Lactobacillus reuteri ATCC PTA 6475 is effective in suppressing disease symptoms caused by EHEC. When germfree Swiss Webster mice are monocolonized with EHEC, they develop disease characterized by weight loss, cecal luminal fluid accumulation, and renal tubular necrosis. When L. reuteri was administered 1 day prior to EHEC challenge and every other day thereafter, EHEC colonization was suppressed and mice were significantly protected from the manifestations of disease. Protection from disease did not require the induction of the antimicrobial compound reuterin in L. reuteri prior to treatment. The twice-daily administration of L. reuteri appeared more effective than every-other-day administration. These data indicated that L. reuteri partially protects mice from disease manifestations of EHEC.

Enterococcal endocarditis associated with crescentic glomerulonephritis.

Glomerulonephritis secondary to infective endocarditis (IE) is an uncommon diagnosis and is usually associated with cardiac valvular infection by blood-culture-positive bacteria. We report a case of necrotizing glomerulonephritis associated with culture-positive endocarditis caused by Enterococcus faecalis. The patient presented with renal abnormalities and was further investigated by renal biopsy. He had immune complex-mediated necrotizing and crescentic glomerulonephritis with mesengial and capillary deposition of immunoglobulin M (Ig M), Ig G, and complement 3 (C3). He was treated with antibiotics, including ampicillin and gentamicin. In addition, steroid and cyclophosphamide were administered. The patient died of renal failure 48 days after hospital admission. In conclusion, glomerulonephritis caused by Enterococcus faecalis endocarditis is an immune-complex-mediated disease characterized by necrotizing and crescentic glomerular lesions that can be fatal despite aggressive antimicrobial and immunosuppressive therapy.

Bilateral renal cortical necrosis in two patients with Neisseria meningitidis sepsis.

Two patients who developed bilateral renal cortical necrosis as a consequence of Neisseria meningitidis infections are described: 1 patient had meningococcemia and the other had meningococcal meningitis. Both patients developed a Shwartzman-like reaction, disseminated intravascular coagulation and irreversible renal failure. Renal biopsy showed sclerosis of the majority of glomeruli; some glomeruli showed capillary congestion, thrombosis and an increased number of neutrophils; the intralobular arterioles showed thrombotic occlusions.