Capnocytophaga canimorsus sepsis in a methotrexate-treated patient with rheumatoid arthritis.

Capnocytophaga canimorsus is a gram-negative rod that can be transmitted primarily by dog bites. This life-threatening organism commonly causes sepsis in patients with splenectomy or alcoholism. A 53-year-old rheumatoid arthritis male treated with methotrexate (MTX) for 5 years was admitted for a 4-day history of fever and dyspnea. He had been bitten on a finger by the family dog 4 days before onset. Laboratory tests revealed pancytopenia, acute renal failure, and evidence of disseminated intravascular coagulation, and he subsequently developed acute respiratory distress syndrome. Furthermore, blood cultures grew gram-negative bacilli and despite intensive treatment, he died 5 days after admission. Later, C. canimorsus was identified from his culture samples using a species-specific polymerase chain reaction. C. canimorsus infections should be considered in the differential diagnosis of sepsis for immunocompromised hosts following animal bites.

Phlegmonous gastritis associated with group A streptococcal toxic shock syndrome.

Phlegmonous gastritis (PG) is a rare, acute, severe infectious disease of the gastric wall that is often fatal due to Streptococcus spp. A 77-year-old man with diabetes and a gastric ulcer was urgently admitted due to prolonged nausea and vomiting. Computed tomography revealed widespread diffuse thickening of the gastric wall, and PG was suspected. The patient expired less than 9 hours after admission despite intensive treatments. Later, an analysis of the blood and gastric juice revealed group A streptococcus (GAS) and virulence factors associated with toxic shock syndrome (TSS). We herein diagnosed a patient with an extremely aggressive course of PG caused by GAS TSS.

Mild clinical course of severe Fever with thrombocytopenia syndrome virus infection in an elderly Japanese patient.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious and hemorrhagic disease recently described in China and western Japan. A 71-year-old healthy Japanese woman noticed a tick biting her after harvesting in an orchard and removed it herself. She developed diarrhea, anorexia, and chills eight days later. Because these symptoms continued, she visited a primary care physician 6 days after the onset. Laboratory data revealed thrombocytopenia, leukocytopenia, and elevated liver enzymes. She was then referred to our hospital. Although not completely fulfilling the diagnostic criteria used in a retrospective study in Japan, SFTS was suspected, and we detected SFTS virus in the patient's blood using RT-PCR. However, she recovered without intensive treatment and severe complications 13 days after the onset. In this report, we present a mild clinical course of SFTS virus infection in Japan in detail.

Fatal diarrheal disease caused by Vibrio cholerae O67 in a patient with myelodysplastic syndrome.

A 71-year-old man with myelodysplastic syndrome (MDS) receiving treatment with azacitidine developed extensive watery diarrhea for three consecutive days. As a result of high-grade dehydration, the patient was urgently admitted to the hospital and fluid replacement therapy was initiated. However, the patient's diarrhea did not improve. Vibrio cholerae non-O1/non-O139 was detected in a fecal culture. On the fourth day, the patient died due to circulatory collapse. An autopsy revealed extensive necrosis of the intestinal mucosa. Vibrio cholerae non-O1/non-O139-induced diarrheal disease often develops in patients with hepatic cirrhosis and has a serious clinical course. We herein report a fatal outcome of Vibrio cholerae O67 infection in an immunocompromised MDS patient.