General Surgery – Renal & Ureteric Calculi MCQs (Part 1)

Xanthogranulomatous Pyelonephritis:

• XGP is a form of chronic bacterial infection of the kidney.
• Most commonly caused by Proteus >E. coli.
• The affected kidney is almost always hydronephrotic and obstructed.

Pyonephrosis:

• Bacterial infection of a hydronephrotic, obstructed kidney, which leads to suppurative                           destruction of the renal parenchyma and potential loss of renal function.
• Kidney is a bag of pus.
• MC cause: Renal stones. Others are infected hydronephrosis, acute pyelonephritis.

• A subcapsular nephrectomy (SN) is sometimes needed to successfully remove the kidney because         of  the dense perinephric adhesions in pyonephrosis.

• The severity of pain is not related to the size of the stone.

Ureteric Colic

• There is a pattern of severe exacerbation on a background of continuing pain
• Radiates to the groin, penis, scrotum or labium as the stone progresses down the ureter.
• The severity of pain is not related to the size of the stone.
• The pain is almost invariably associated with haematuria.
• There may be few physical signs.

Chronic pyelonephritis is so often associated with vesicoureteric reflux that some feel that it is better named “Reflux nephropathy”. It is important cause of renal damage and death from end-stage renal failure.

• MC cause of ureteric obstruction: Stone.
• MC cause of ureteric colic in haematuria: Clot

Emphysematous Pyelonephritis

• Necrotizing infection characterized by the presence of gas within the renal parenchyma or perinephric tissue.
• About 80–90% of patients have diabetes, rest are associated with urinary tract obstruction from     calculi or papillary necrosis, more common in females
• Bacteria most frequently cultured from the urine include E. coli (MC), Klebsiella pneumoniae,          and Enterobacter cloacae.
• Decreased host immunity is most important factor.                                                                      Clinical Features:
• Triad “Fever, flank pain, and vomiting” almost always present and fails initial management with      parenteral antibiotics.
• Pneumaturia may be present.
• The mortality rate is 19–43%.                                                                                                        Diagnosis:
• Plain X-ray: Gas overlying the affected kidney.
• CT scan is more sensitive than USG in detecting the presence of gas in the renal parenchyma
Management.
• Fluid resuscitation, prompt control of blood glucose and relief of urinary obstruction is essential with parenteral antibiotics (3-4 weeks).
• In addition, percutaneous drainage is helpful in accelerating resolution of the infection and minimizing the morbidity and mortality of the infection.
• Most cases require nephrectomy.
Prognosis:
• Poor prognostic factors: High creatinine, low platelet, presence of renal/perirenal fluid with a bubbly/loculated gas pattern or gas in the collecting system.