Neutrophilic dermatosis-associated sterile chronic multifocal osteomyelitis in pediatric patients: Case report and review

Atypical pyoderma gangrenosum (PG) and Sweet syndrome are neutrophilic derm atoses that share some common features. Sterile chronic recurrent multifoca l osteomyelitis is a rare association of these neutrophilic dermatoses that has only been reported in children. We report a 3-year-old girl who initia lly presented with pain in her left hand and right leg. Roentgenograms and bone scan revealed findings of multifocal osteomyelitis affecting both femu rs, the right tibia, left clavicle, right eighth costochondral junction, an d left ulna. She was treated with antibiotics without improvement. Bone bio psy of the left ulna revealed histologic changes consistent with osteomyeli tis, however, all cultures for bacteria, mycobacteria, and fungi were negat ive. She subsequently developed an ulcer surrounded by a violaceous, underm ined border at the site of the bone biopsy, which also did not improve duri ng antibiotic treatment. A biopsy specimen from this lesion demonstrated a dense perivascular and periappendageal infiltrate of neutrophils within the dermis and edema of the papillary dermis compatible with a neutrophilic de rmatosis. She was treated with oral prednisone which resulted in resolution of skin lesions, bone pain, and soft tissue swelling. This case further do cuments the association between PG or Sweet syndrome and multifocal sterile osteomyelitis.