Sarcomere length of the vastus intermedius with the knee joint angle change.

The force-length relation of the skeletal muscles is an important factor influencing the joint torque at a given joint angle. We aimed to clarify the relationship between the resting sarcomere length and knee joint angle in the vastus intermedius (VI) and to compare it with that of the vastus lateralis (VL). The left and right legs were fixed at knee joint angles of 0° and 90°, respectively, in seven cadavers (age at the time of death: 70-91 years). Muscle tissues were dissected by necropsy of the VL and the VI, and electron microscopy images were obtained to calculate the sarcomere length. At knee joint angles of 0° and 90°, the VL sarcomere length was 2.28 ± 0.49 µm and 2.30 ± 0.48 µm, respectively, and the VI sarcomere length was 2.19 ± 0.35 µm and 2.46 ± 0.53 µm, respectively, with a significant difference between the two (p = 0.028). The magnitude of sarcomere length changes with knee joint angle changes was significantly greater for the VI (0.27 ± 0.20 µm) than for the VL (0.02 ± 0.09 µm) (p = 0.009). Thus, knee joint angle changes may affect the passive and active tension produced by the VI more than those produced by the VL.

Intestinal perforation by a peritoneal dialysis catheter in which fungal peritonitis led to diagnosis: a rare case report.

Intestinal perforation by a peritoneal catheter is an uncommon, but serious, complication that has a high mortality rate. Intestinal perforation in peritoneal dialysis (PD) patients is difficult to diagnose using symptoms and radiological findings, which may result in a delay in diagnosis. Moreover, intestinal perforation complicated with fungal peritonitis is reportedly a severe condition with a poor prognosis. Herein, we report the case of a 78-year-old man on PD, whose diagnosis of perforative peritonitis was difficult to diagnose preoperatively. He was transferred to our hospital complaining of relapsing PD-related peritonitis due to Klebsiella oxytoca infection 2 months after the insertion of the PD catheter. He had been treated with various antibiotics in the previous hospital. Over the course of treatment, he complained of diarrhea, which was diagnosed as acute enteritis. Upon admission to our hospital, he had no abnormal clinical signs except for a cloudy PD effluent. Blood examination showed a high C-reactive protein level (8.41 mg/dL), a white blood cell count in the PD fluid of 367 cell/µL (neutrophils 55.1%), and the presence of Candida parapsilosis. We initiated antifungal therapy and, during catheter removal, found evidence of intestine perforations by the PD catheter, which were successfully repaired. After catheter removal and intestine repair, he recovered and was discharged to continue undergoing hemodialysis. Based on our case, we recommend that intestine perforations should be considered as a cause of relapsing PD-related peritonitis with abdominal symptoms, particularly watery diarrhea. Furthermore, catheter removal and antifungal administration should be initiated earlier after the diagnosis of fungal peritonitis.

Proliferative glomerulonephritis with monoclonal immunoglobulin A light-chain deposits in the renal allograft.

We herein describe the unique case of a 59-year-old man who underwent living kidney transplantation for IgA nephropathy (IgAN) and developed progressive kidney failure associated with the appearance of proliferative glomerulonephritis. An early protocol biopsy revealed recurrent IgAN with mesangial IgA2 deposits restricted to a single immunoglobulin λ light-chain isotype. Despite treatment with tonsillectomy and rituximab, the patient eventually lost his allograft 31 months after transplantation. Serum electrophoresis showed a monoclonal IgA pattern. This case might share common pathological characteristics with the newly described entity referred to as proliferative glomerulonephritis with monoclonal IgG deposits.