Xanthogranulomatous osteomyelitis of the humerus in a pediatric
patient with Alagille syndrome: a case report and literature
Received: 3 April 2017 /Revised: 26 May 2017 /Accepted: 19 June 2017 /Published online: 28 June 2017
Abstract Xanthogranulomatous osteomyelitis (XO) is an ex-
ceedingly rare disease characterized by infiltration of histio-
cytes and foamy macrophages. Both on gross examination
and on radiographs, XO can mimic malignancy. We describe
the case of a 5-year-old female with Alagille syndrome who
presented with a pathologic fracture of the right humerus.
Initial radiographs revealed multiple osteolytic lesions in the
distal humerus while MRI showed a large soft tissue mass.
Biopsy confirmed the diagnosis of XO, which has hitherto not
been described in a patient with Alagille syndrome. The pa-
tient was admitted for IVantibiotics and taken to the operating
room for an incision and debridement. Tissue cultures were
obtained and grew Salmonella. Antibiotic therapy was ta-
pered, and the patient responded to treatment. She was doing
well at her 6-month follow-up visit. In the discussion section,
we explore how osteopenia and immune dysregulation caused
by Alagille syndrome can affect the development of XO. We
summarize all previously reported cases of XO and conclude
that XO presents as an osteolytic lesion that expands rapidly
over the course of a few weeks. We highlight that XO can
mimic sarcoma because of its mass effect but can be distin-
guished radiographically by the presence of surrounding scle-
rosis. Given the rapid onset of XO, we classify it as an acute
osteomyelitis. We discuss how leukemia and Ewing sarcoma
can present similarly to acute osteomyelitis. We then empha-
size key features that can be used to distinguish these malig-
nancies from acute osteomyelitis.
Keywords Xanthogranulomatous osteomyelitis
Xanthogranulomatous inflammation is a rare entity. It primar-
ily entails the infiltration of macrophages and histiocytes into
the affected tissues. These cells release cytokines and recruit
additional immune cells, all of which coalesce to produce a
potent inflammatory response that can result in areas of hem-
orrhage and purulence .
Xanthogranulomatous inflammation usually presents in
soft tissues. Historically, it has been described primarily in
the gallbladder and kidneys where it manifests as cholecystitis
and pyelonephritis, respectively [2, 3]. More recent literature
has demonstrated evidence of xanthogranulomatous inflam-
mation in the lung, gastrointestinal tract, bladder, and
male/female urogenital tracts . Although its presenting
symptoms vary based on the location, the histopathology is
uniform, characterized by sheets of foamy histiocytes .
While xanthogranulomatous inflammation is a rare diagno-
sis in soft tissues, it is found even less commonly in bone.
Xanthogranulomatous osteomyelitis was initially described
by Cozzutto in 1984, and since then only 14 other cases of
XO have ever been reported in the English literature .
In this case report, we describe the first case of XO in a
patient with Alagille syndrome. We discuss how unique
characteristics of Alagille syndrome may contribute to the
formation of XO. We detail all previous cases of XO and
identify their distinct radiographic and clinical features.
* Adnan Cheema
Department of Orthopedic Surgery, University of Pennsylvania, 3737
Market St, Philadelphia, PA 19104, USA
Department of Orthopedic Surgery, Children’s Hospital of
Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA 19104, USA
Department of Pathology, Children’s Hospital of Philadelphia,
5NW11, 3401 Civic Center Blvd, Philadelphia, PA 19104, USA
Skeletal Radiol (2017) 46:1447–1452