Bartonella henselae Hepatic Abscesses and Associated Osteomyelitis in a Pediatric Patient.

Bartonella henselae is a Gram-negative bacillus transmitted to humans via cat saliva or scratch. Cat scratch disease, the typical clinical manifestation of B. henselae infection, presents as localized cutaneous or regional lymphadenopathy. Rare, atypical presentations, generally reflecting bloodborne disseminated disease, can include hepatosplenic, cardiac, ocular, neurologic, or musculoskeletal involvement. Here, we present a case of disseminated B. henselae with hepatic abscesses and associated ischial osteomyelitis in an immunocompetent 2-year-old male patient. Although osteomyelitis is a rare manifestation of B. henselae infection, it should be included in the differential diagnosis in pediatric patients presenting with fever of unknown origin and musculoskeletal pain, especially in the setting of cat exposure. Hepatic involvement of B. henselae infection is associated with significant morbidity; therefore, abdominal imaging is critical in the diagnostic workup. This patient was successfully treated after a 6-week course of azithromycin and rifampin, as evidenced by symptom resolution and improved fluid collections on repeat imaging. While most cases of B. henselae resolve without treatment, in severe or disseminated infection such as this case, antibiotics such as azithromycin and rifampin should be considered for treatment.

Coadministration of Immunosuppressant Treatments With Pegloticase in the Context of Solid-Organ Transplantation and Gout: A Case Report.

Refractory gout can be treated with infusions of pegloticase, which metabolizes uric acid into a product readily excreted in urine. Antidrug antibodies often develop, leading to reduced efficacy and potential infusion reactions. The concomitant administration of immunosuppressive agents has been suggested as a means of mitigating the effects of drug-related immunogenicity, rendering treatment more tolerable, and resulting in better outcomes. This report presents cases of 2 patients with tophaceous gout, each having previously undergone a solid-organ transplant, each taking immunosuppressants to prevent organ rejection, and each successfully treated with pegloticase. Although data from randomized controlled studies are needed, these cases suggest that it may be beneficial to coadminister an immunosuppressive medication to extend drug persistence with pegloticase in the management of refractory gout. This approach could allow patients to receive long-term treatment, resulting in improved patient outcomes.