Pyonephrosis: epidemiological, clinical, and therapeutic aspects at Aristide Le Dantec University Hospital Centre (Dakar)

Abstract

Introduction: Pyonephrosis is most often secondary to an obstruction in the urinary excretory tract. It is a serious condition that can be life-threatening due to septic shock as well as functionally life-threatening due to the destruction of the renal parenchyma. Our study aimed to analyse the epidemiological, clinical, and therapeutic aspects of pyonephrosis at the Urology Department of the Aristide Le Dantec University Hospital Centre (CHU).

Materials and methods: This was a retrospective study of 82 patients followed up for pyonephrosis in the Urology-Andrology Department of the Aristide Le Dantec CHU from 1 January 2005 to 31 December 2021. The parameters studied were the epidemiological, clinical, and therapeutic aspects of pyonephrosis.

Results: The annual incidence was 5.1 ± 3.4 patients. The mean age was 44 ± 15.6 years. The mean time to diagnosis was 24.5 ± 8.7 months. Lower back pain and low-grade fever were the symptoms at presentation, with respective percentages of 87.2 % and 69.8%. Fever and lower back pain were the most frequent signs identified in clinical examination, with percentages of 64.6% and 65.8%, respectively. Escherichia coli and Klebsiella pneumoniae were the most frequent germs detected by cytobacteriological examination of urine (CBEU). Pseudomonas aeruginosa and Bacteroides spp. were the most frequent germs found in the cytobacteriological examination of pus. Urotomodensitometry (Uro-CT), performed in 57.3% of patients (n = 47), led to a diagnosis of pyonephrosis in 89.3% of patients (n = 42). Urinary lithiasis was the main cause of renal parenchymal destruction. Nephrectomy was performed in 70.7% of patients (n = 58). It was preceded by nephrostomy in 52.4% of cases (n = 43), coupled with bi-antibiotherapy. Extracapsular nephrectomy was the most common procedure, accounting for 84.5% (n = 49). Intraoperative events were noted in 25 patients. Peritoneal and pleural injuries predominated. Conservative treatment was instituted in 26.8% of patients. The average hospital stay was 7.3 ± 10.2 days. The global rate of complications was 4.87% and mortality was 3.65%.

Conclusion: The long consultation time means that the main treatment modality remains nephrostomy followed by nephrectomy or nephrectomy from the outset, and does not often allow conservative treatment.