Detection of metallo-ß-lactamase genes in clinically isolated Klebsiella pneumoniae and Klebsiella oxytoca.

We detected and characterized metallo-ß-lactamase genes (blaIMP-1 and blaIMP-11) in third generation cephalosporin-resistant Klebsiella pneumoniae and Klebsiella oxytoca isolated at Showa University Hospital between January 1, 2011 and December 31, 2012. The cephalosporin-resistant K pneumoniae strains were frequently isolated from the urine, while one strain of K. pneumoniae, which was resistant to carbapenem, was isolated from the stool. We analyzed the phenotypes and genotypes of the metallo-ß-lactamase genes from the 16 strains of cephalosporin-resistant-K pneumoniae and 6 strains of -K. oxytoca isolated from the same ward. The minimum inhibitory concentrations of imipenem were below 4 µg/ml in 21 out of the 22 isolated strains. The double disc synergy test using ceftazidime and sodium mercaptoacetic acid revealed enlargements in the inhibitory zones of 14 of the 16 strains of K. pneumoniae and all 6 strains of K. oxytoca. Metallo-ß-lactamase genes were detected in all of the tested strains, with blaIMP-1 in 3 K. pneumoniae and 1 K. oxytoca, blaIMP-11 in 13 K pneumoniae and 4 K. oxytoca, and both blaIMP-1 and blaIMP-11 in one K. oxytoca. Our results indicate that third generation cephalosporin-resistant and imipenem-susceptible K. pneumoniae and K. oxytoca possess the metallo-ß-lactamase gene. The active surveillance of metallo-ß-lactamase genes should be performed in clinical laboratories. (Original).

Characteristics and predictors of post-transplant-associated hemophagocytic lymphohistiocytosis in adults.

Hemophagocytic lymphohistiocytosis (HLH) is an uncontrolled hyperinflammatory disorder driven by an overactive immune system that results in high mortality. Post-transplant-associated hemophagocytic lymphohistiocytosis (PT-HLH) is a type of secondary HLH that occurs following allogeneic hematopoietic stem cell transplantation (allo-HSCT). The clinical features of PT-HLH remain unclear and diagnostic and prognostic tools have not yet been established. Here, we retrospectively evaluated the clinical manifestations and outcomes of PT-HLH in 94 patients who underwent allo-HSCT. According to our PT-HLH criteria (hyperferritinemia and increased macrophage count in bone marrow), PT-HLH occurred in 12 patients (12.8%). The PT-HLH patients showed splenomegaly (P = .001), a higher risk of engraftment failure (P = .013), and an increased percentage of macrophages and hemophagocytes in bone marrow aspirates (P = .0009 and P = .0006, respectively). Moreover, univariate and multivariate analyses revealed that the survival rate was lower in PT-HLH patients than non-PT-HLH patients (P = .0017 and P = .034, respectively). This study defines the clinical features of PT-HLH and PT-HLH criteria that could be useful tools for diagnosing PT-HLH.

[Salmonella enteritidis osteomyelitis of the tibia--a case report and review of literature on Salmonella osteomyelitis of Japanese patients].

We described a rare case of Salmonella enteritidis osteomyelitis of the tibia combined with arthritis of the ankle joint. A 4-year-old, otherwise healthy girl was hospitalized with 9-day history of fever, left leg pain, and diarrhea. On admission, her left lower leg and ankle were markedly reddened and swollen. Laboratory examinations disclosed a WBC of 16,300/microliter and a C-reactive protein of 15.6 mg/dl. A T2-weighed magnetic resonance image of the leg depicted a high intensity area around the left distal tibia and an extremely high intensity fluid in her left ankle joint, leading to our diagnosis of purulent osteomyelitis of the tibia and arthritis of the ankle joint. Salmonella enteritidis was isolated from ankle joint fluid and later aspirated bone marrow of the tibia, but not from blood or stool. Because of poor response to intravenous treatment with panipenem/betamipron for 2 days, she underwent drainage and washing of the joint fluid, and intramedullary administration of cefotaxime and ampicillin. She completely recovered without sequelae following treatment with sensitive antibiotics for 4 weeks in total. There has not been any relapse for more than 1.5 years. The authors also bibliographically surveyed the literature published from 1966 to 2002 and found 35 Japanese patients with Salmonella osteomyelitis. The present patient was the second case caused by Salmonella enteritidis in Japan. Septic arthritis is a rare complication, accounting for only 8% of the patients. Since Salmonella enteritidis has been a leading serotype among human isolates of Salmonella species during the past decade, it would be warranted to determine whether osteomyelitis due to this organism is likely to increase.

Chromosomal mapping of hyperserum IgA and glomerular IgA deposition in a high IgA (HIGA) strain of DdY mice.

BACKGROUND: The high IgA (HIGA) strain of ddY mice is an inbred model of IgA nephropathy (IgAN), established by selective mating of outbred ddY mice. HIGA mice show high levels of serum IgA and glomerulonephritis with mesangial IgA deposition. To identify the genetic loci responsible for hyperserum IgA and glomerular IgA deposition in this strain, quantitative trait loci analysis was carried out. METHODS: By crossing HIGA with BALB/c mice, 244 F2 generations were produced. Serum IgA levels and glomerular IgA deposition were examined at 40 weeks of age. Genetic markers were typed at 105 microsatellites and the quantitative trait loci of hyperserum IgA and glomerular IgA deposition were confirmed using Map Manager QTX software. RESULTS: Two significant quantitative trait loci of hyperserum IgA were identified on chromosome 2 [logarithm of odds (LOD) = 5.01] and chromsome 4 (LOD = 4.45), and a suggestive quantitative trait locus of hyperserum IgA was located on chromosome 1 (LOD = 3.49). On chromosome 15, a significant quantitative trait locus of glomerular IgA deposition was identified (LOD = 4.40) without the hyperserum IgA locus. Serum IgA level was weakly correlated with the intensity of glomerular IgA in 244 F2 mice; however, the quantitative trait loci of hyperserum IgA were not significantly associated with glomerular IgA deposition. CONCLUSION: These findings indicate that, in HIGA mice, glomerular IgA deposition is mainly regulated by a quantitative trait locus on chromosome 15, and hyperserum IgA synergistically but weakly affect glomerular IgA deposition. The immune disturbance similar to IgAN was revealed to be under multigenic control in HIGA mice.