Primary Pyogenic Abscess in an Immunocompetent Child: An Indian Perspective.

Introduction: Pyogenic psoas abscess (PPA) is a rare but severe condition. Previously linked to tuberculosis, it's now seen with diverse causes. This case report details the diagnosis and management of PPA in a healthy Indian child, initially suspected of having hip issues. Case Report: A 5-year-old girl was brought for pain in her right hip and lower back, and fever for 3 days. She was irritable and unable to walk. She was febrile (101°F), irritable, and toxic with her right lower limb flexed 30° at the hip with all its movements restricted and painful. Inguinal lymph nodes were palpable. Blood tests showed elevated white blood cell count (18,000 × 109/L) and inflammatory markers, with a negative Mantoux test. Radiographs of the lumbosacral spine were normal. Magnetic resonance imaging showed a large abscess in the right psoas and iliacus muscles, measuring 6.8 × 3.3 × 3 cm. She underwent open drainage through a retroperitoneal approach, and samples were sent for bacteriological analysis. The wound was irrigated and closed over a drain.Post-operatively, she received Linezolid being culture positive for methicillin-resistant Staphylococcus aureus. Her pain reduced by the 3rd day and she was discharged with oral antibiotics. She walked at 6 weeks and was symptom-free on follow-up. Conclusion: This case highlights the crucial need to consider PPA in children showing hip pain, limping, and infection signs. Due to its subtle presentation and similarity to septic arthritis, high suspicion is essential. Timely imaging and proper treatment, such as drainage and antibiotics, can ensure positive results.