A missed psoas abscess diagnosis: A forensic case report.

Psoas abscess is a rare pathology that usually presents with non-specific signs and rare clinical features. These characteristics can delay the diagnosis leading to complications and death. We report a forensic autopsy case of a 65-year-old male, alcoholic, smoker, with a history of hypertension, and urinary infection, who presented to the emergency room for anorexia and consciousness disorder. On physical examination, the patient was febrile and confused. Laboratory exams revealed leukocytosis and elevated C-reactive protein (CRP). Two days later, he died despite extensive resuscitation. Forensic autopsy revealed a large amount of green pus in the left psoas muscle extending to the muscles of the thigh of the same side with multiple cavities. The pus extended to the left kidney with destructive parenchyma and coralliform lithiasis. Histological examination showed destroyed renal tissue by lesions of chronic and acute pyelonephritis with dilatation of the pyelocaliceal cavities. Bacteriological analysis of the pus showed the presence of Escherichia coli. The psoas abscess was secondary to pyonephrosis favored by the immunodeficiency. Thus, death was attributed to a septic shock secondary to a psoas abscess complicating pyonephrosis.

Hounsfield unit attenuation value can differentiate pyonephrosis from hydronephrosis and predict septic complications in patients with obstructive uropathy.

We aimed to assess the role of computerized tomography attenuation values (Hounsfield unit-HU) for differentiating pyonephrosis from hydronephrosis and for predicting postoperative infectious complications in patients with obstructive uropathy. We analysed data from 122 patients who underwent nephrostomy tube or ureteral catheter placement for obstructive uropathy. A radiologist drew the region of interest for quantitative measurement of the HU values in the hydronephrotic region of the affected kidney. Descriptive statistics and logistic regression models tested the predictive value of HU determination in differentiating pyonephrosis from hydronephrosis and in predicting postoperative sepsis. A HU cut-off value of 6.3 could diagnose the presence of pyonephrosis with 71.6% sensitivity and 71.5% specificity (AUC 0.76; 95%CI: 0.66-0.85). At multivariable logistic regression analysis HU ≥ 6.3 (p ≤ 0.001) was independently associated with pyonephrosis. Patients who developed sepsis had higher HU values (p ≤ 0.001) than those without sepsis. A HU cut-off value of 7.3 could diagnose the presence of sepsis with 76.5% sensitivity and 74.3% specificity (AUC 0.79; 95%CI: 0.71-0.90). At multivariable logistic regression analysis, HU ≥ 7.3 (p ≤ 0.001) was independently associated with sepsis, after accounting for clinical and laboratory parameters. Measuring HU values of the fluid of the dilated collecting system may be useful to differentiate pyonephrosis from hydronephrosis and to predict septic complications in patients with obstructive uropathy.

TcpC secreting uropathogenic E. coli promoted kidney cells to secrete MIP-2 via p38 MAPK pathway.

Pyelonephritis is an infection of the upper urinary tract with characteristic histological change to neutrophil infiltration in the kidney. The majority of pyelonephritis is caused by uropathogenic Escherichia (E.) coli (UPEC) bearing distinct virulence factors. Toll/interleukin­1 receptor domain­containing protein C (TcpC) encoded by E. coli is an important virulence factor in the majority of strains of UPEC and inhibits macrophage­mediated innate immunity, which serves an essential role in the pathogenesis of pyelonephritis. In the present study, it was demonstrated that TcpC induced kidney cells to produce macrophage inflammatory protein­2 (MIP­2; also known as C­X­C motif chemokine 2). MIP­2 concentration in kidney homogenates from TcpC­secreting UPEC CFT073 (TcpCwt) murine pyelonephritis models was significantly higher compared with that in kidney homogenates from tcpC knockout CFT073 (TcpC­/­) models. In vitro, TcpCwt dose­dependently promoted MIP­2 secretion in HEK­293 cells. The concentration of MIP­2 in culture supernatants of HEK­293 co­cultured with TcpCwt was profoundly higher compared with that of HEK­293 co­cultured with TcpC­/­. In the presence of anti­TcpC antibody, the enhancement effect of TcpCwt on MIP­2 production was completely abrogated, suggesting that the enhanced production of MIP­2 was mediated by secreted TcpC. Furthermore, it was demonstrated that TcpC­/­ treatment had no effect on the p38 mitogen activated protein kinase (MAPK) signaling pathway, while TcpCwt treatment resulted in the activation of p38 MAPK in HEK­293 cells, as indicated by a simultaneous increase in p38 and phosphorylated­p38. In addition, inhibition of p38 MAPK with SB203580 significantly decreased MIP­2 concentration and neutrophil recruitment activity in the supernatants of HEK­293 cells co­cultured with TcpCwt. This indicates that TcpC may promote MIP­2 production in kidney cells through the p38 MAPK signaling pathway. Taken together, the data of the present study demonstrated that TcpC can induce MIP­2 production, which may contribute to the characteristic histological change associated with pyelonephritis. This data has provided novel evidence to further clarify the pathogenesis of pyelonephritis and novel directions on the pathogenicity of TcpC­secreting UPEC.

Pyonephrosis due to Chryseobacterium gleum: a first case report.

Chryseobacterium spp are widely distributed in nature but data of their isolation from clinical samples is scanty. Here, we report the first case of AmpC producing C. gleum causing pyonephrosis in a patient having bilateral nephrolithiasis on double J (DJ) stent. The present isolate was resistant to vancomycin, erythromycin, clindamycin, carbapenems and ciprofloxacin and susceptible to tetracycline and minocycline. The patient was treated with tetracycline and recovered without the need for removal of the DJ stent. The environmental surveillance carried out to trace the nosocomial origin of the isolate was negative. Since antimicrobial susceptibility of this isolate is different from previous reports, we emphasise that in vitro susceptibility testing should be sought to choose optimal antimicrobial agents for these Nonfermentative Gram-Negative Bacilli (NFGNBs) with different susceptibility patterns.

[Retroperitoneoscopic surgeries for pyoinflammatory diseases of the kidney with varying severity of endotoxemia].

The medical histories of 98 patients with pyoinflammatory diseases of the kidney, who underwent surgery by retroperitoneoscopic access, and 75 patients, who underwent traditional open surgery were analyzed. The degrees of multiple organ dysfunction and endotoxemia were determined in all patients. The groups were comparable in terms of clinical manifestations and severity of intoxication. The advantages of minimally invasive retroperitoneoscopic interventions are demonstrated; they allow to reduce the surgical morbidity, pain after surgery, the frequency and severity of intraoperative complications, length of in-hospital stay, the period of disability, the cost of treatment, and the need for medications.