Purpose or Case Report: The purpose is to educate the reader about the clinical impacts of radiology reporting prior to pathologic diagnosis. We will discuss a 19-month-old patient’s clinical picture of malignancy with ultimate pathologic diagnosis of disseminated coccidioidomycosis (cocci) and review findings of this disease. Review of biopsy technique and discussion on what specimens should be sent for will also be provided.
Methods & Materials: Our patient is a previously healthy 19-month-old African American male born in a region endemic to cocci. He presented with bumps on his head, fever and limping. Initial imaging showed lytic calvarial lesions and a lucent calcaneus lesion. After evaluation, the patient’s differential diagnosis was langerhan cell histiocystosis, metastatic neuroblastoma, metastatic sarcoma, lymphoma/leukemia, or subacute osteomyelitis. On brain MRI the patient was found to have expansile skull lesions with concern for dural involvement. The whole body MRI revealed an enhancing lung mass with enhancing lesions involving the olecranon, iliac crest, and posteromedial ribs involving the pedicles and spinal canal. Pediatric Interventional Radiology (IR) was consulted to obtain a biopsy. The lytic calcaneal lesion was biopsied and pathology returned as cocci, negative for malignancy. The patient was diagnosed with disseminated cocci, started on antifungal therapy and discharged home.
Results: Bone biopsies are a routine procedure performed by pediatric IR. The most frequent indication for bone biopsy is to determine if metastatic disease is present. Typically bone biopsies are performed with CT in order to precisely localize the lesion and determine the best route to the lesion avoiding vascular and neural structures. Soft tissue and lytic lesions may be biopsied with a 14- to 18- gauge coaxial biopsy gun while densely ossified lesions will require a bone drill. The incidence rate of bone biopsy complications approaches 2% with the major complication being infection.¹
Conclusions: Cocci is a fungal infection endemically occurring in the Southwest that occurs after inhalation of airborne spores. Approximately 60% of those infected are asymptomatic however cocci is known as the great imitator due to a variety of clinical presentations.^2,3 Skeletal cocci is a rare diagnosis that can be seen in the <1% of persons diagnosed with disseminated cocci.^2,4 The diagnosis can be missed or delayed resulting in extensive medical workup.⁴ Overall the key to diagnosing musculoskeletal cocci is bone biopsy.²