Pyomyositis during induction chemotherapy for acute lymphocytic leukemia.
OBJECTIVE
Pyomyositis is a rare disease in temperate climate regions and frequently has a subacute presentation. Because of this, the entity is often misdiagnosed.


METHODS
Two boys with acute lymphocytic leukemia (ALL) who presented with muscle pain, shortly after receiving induction chemotherapy, were evaluated.


RESULTS
Presenting physical examination and laboratory findings were unremarkable except for extremity pain and tenderness. These symptoms were initially attributed to a neurotoxic side effect of vincristine. As the children's symptoms progressed, muscle abscess formation was finally delineated by gallium and computed tomography scans, and the diagnosis of pyomyositis was made. In both cases, the invading organism was Staphylococcus aureus. Both children responded well to incision and drainage of the abscesses and antibiotic therapy.


CONCLUSIONS
Four cases of pyomyositis occurring in ALL patients shortly after induction chemotherapy have now been described. We feel that when children from this population present with muscle pain, pyomyositis should be part of the differential diagnosis. With early medical and surgical intervention, morbidity and mortality can be avoided.
Corden
T E
TE
Department of Pediatrics, Strong Children's Medical Center, Rochester, New York 14642-8667, USA.
Morgan
E R
ER
D000038:Abscess / Q000209:etiology / Q000628:therapy*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects*; D001215:Asparaginase / Q000008:administration & dosage; D001424:Bacterial Infections / Q000209:etiology / Q000628:therapy*; D002648:Child; D003630:Daunorubicin / Q000008:administration & dosage; D004359:Drug Therapy, Combination / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D009135:Muscular Diseases / Q000209:etiology / Q000628:therapy*; D010068:Oxacillin / Q000627:therapeutic use*; D010146:Pain; D010406:Penicillins / Q000627:therapeutic use*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D011241:Prednisone / Q000008:administration & dosage; D012074:Remission Induction; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000209:etiology; D014750:Vincristine / Q000008:administration & dosage
D010406:Penicillins; D014750:Vincristine; D001215:Asparaginase; D010068:Oxacillin; D011241:Prednisone; D003630:Daunorubicin