A young male saw his general practitioner because of lower back pain, limpness, nightly sweating, subfebrilia, and weight loss. Further diagnostics showed that he had a primary psoas abscess. Psoas abscesses are categorized as primary and secondary. Primary psoas abscess is a rare disease in Europe and North America. It is primarily seen in young men, and the classical symptom-triad is: fever, back pain, and limpness. The golden standard diagnostic tool is computed tomography, and treatment involves appropriate antibiotics, which can be combined with percutaneous drainage.