Lymphoma is the seventh most common type of malignancy in both males and females. It may develop in any location where lymphomatous tissue exists. Although extranodal presentation in the lower limb and pelvis are uncommon, it could present with diverse manifestations. We report an unusual case of primary extranodal large B-cell lymphoma of the ankle joint initially presumed to be a chronic osteomyelitis. This case report discusses the impact of imaging studies on decision-making and highlights the need to consider malignancy in chronic infections.

Lumbo-pelvic pain is a common and non-specific problem during pregnancy and postpartum. Although perinatal pyogenic sacroiliitis is uncommon during this time, it might be difficult to distinguish from reactive sacroiliitis in women who are experiencing significant lower back and pelvic girdle pain, as the symptoms and signs are not clear and the tests are not definitive. A 34-year-old primigravida went to the emergency department with severe lower back pain radiating to the right gluteal region and down to the back of the right thigh. This pain began 12 days prior to her presentation and eventually worsened to the point that she could not stand or walk. Her vital signs were within normal ranges, and she was experiencing a fever. Apart from a slight widening of the symphysis pubis, her pelvic and lumbo-sacral pain X-rays revealed no important findings. With the clinical impression of right lumbo-pelvic pain, the patient was admitted for pain management and further inquiries. Despite the fact that the antibiotherapy was prescribed to treat a urinary tract infection, the significant recovery of the patient’s symptoms, even in the absence of a definitive culture of aspirate from the right sacroiliac joint, supported the diagnosis of pyogenic sacroiliitis.

Background: Lumbo-pelvic (LPP) pain is common and non specific problem during pregnancy and post partum. Despite the fact that perinatal pyogenic sacroiliitis (PSI) during this period is rare, it should be considered as a vital differential diagnosis in women who have debilitating lower back and pelvic girdle pain. Case: A 34 years old primigravida presented to the emergency department with extreme right sided lower back pain radiating to the right gluteal region and down to the back of the right thigh. This pain began twelve days prior to her presentation and eventually worsened to the point that she couldn't stand or walk. Her vital signs were within normal limits, and she was febrile. Apart from a slight widening of the symphysis pubis, her pelvic and lumbo-sacral plain x-rays revealed no important findings. With the clinical impression of right LPP, the patient was admitted for pain management and further inquiries. Conclusion: Despite the fact that lower back and pelvic girdle pain are normal throughout pregnancy and the postpartum period, perinatal PSI is uncommon. It's a tough diagnosis to make because the symptoms and signs aren't clear, and the tests aren't definitive. When pathognomonic clinical and radiologic signs indicate an infectious process and isolation of pathogenic bacteria is not possible, medical management with empirical antibiotics should not be delayed.