Acute Pyelonephritis

Acute pyelonephritis is a severe bacterial infection of the renal pelvis and kidney parenchyma, most commonly caused by Escherichia coli. It typically results from ascending urinary tract infections but may also occur through hematogenous spread. Risk factors include urinary obstruction, vesicoureteral reflux, diabetes mellitus, and immunosuppression. Patients usually present with fever, flank pain, dysuria, and systemic signs of infection. Diagnosis is based on clinical features, urinalysis, urine culture, and imaging in complicated cases. Early empiric antibiotic therapy is essential, followed by targeted treatment based on culture sensitivity. Preventive measures include proper hygiene, management of underlying conditions, and in some cases, prophylactic antibiotics. Disease recognition and treatment are crucial to prevent complications such as renal scarring, abscess formation, and sepsis.