Primary bone lymphomas thought to be osteomyelitis urgently demand a rapid diagnosis in bone pathology.

We describe in detail three cases of primary bone lymphoma (PBL), initially treated as osteomyelitis of unknown etiology. These cases show which difficulties can occur with diagnosing this entity and highlight the urgent need for rapid diagnostic results in the field of bone pathology. Case 1: A 22-year-old man with the very rare diagnosis of precursor B-lymphoblastic lymphoma in the tibia (previously published). Case 2: A 13-year-old boy with an anaplastic large cell lymphoma of the "os pubis". With initial diagnosis pointing to multifocal osteomyelitis, histology of the left iliac crest revealed a florid/chronic osteomyelitis. During clinical regression with a new osteolytic lesion, he received treatment for chronic recurrent multifocal osteomyelitis. Case 3: A 60-year-old man with an anaplastic large cell lymphoma of the right sacrum, accompanied by a putrid, florid/chronic osteomyelitis. At first, an incisional biopsy revealed a florid/chronic osteomyelitis-only.

Osteitis or osteomyelitis of the pubis? A diagnostic and therapeutic challenge: report of 9 cases and review of the literature.

Osteitis pubis is a noninfective inflammation of the symphysis pubis, without distinct aetiology. It has often been reported after urological or gynaecological procedures, and is also associated with trauma, rheumatic disorders, pregnancy and parturition. Symptoms mostly resolve spontaneously. On the other hand, osteomyelitis of the pubis is a classical infective inflammation of bone. The differential diagnosis between both entities may be difficult. The most common complaint in both inflammatory diseases is pain under load, either local or pseudoradicular in nature. The biochemistry is normal or slightly inflammatory in osteitis pubis, but frankly inflammatory in osteomyelitis. A 3-phase bone scan may be positive in the mineralisation or delayed phase in case of osteitis, and in all three phases in case of osteomyelitis. Aspiration is the ultimate diagnostic test: in case of osteomyelitis pubis, culture of the aspirate will usually lead to the diagnosis, sometimes even after antibiotic therapy.