Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/15/2005
Publication Date: 9/15/2005
Citation: Reust, C., Tieszen, M., Duhancik, T., Lawaczeck, E., Singh, V., Cage, G., Mathison, B., Clark, E., Bricker, B.J. 2005. A Rare Case of Brucella canis in an HIV-Infected Patient [abstract].
Technical Abstract: Presentation: A 46-year-old HIV-infected woman was admitted with a three-day history of high fever, diffuse arthralgias, malaise, and loose stools. History: The patient had been diagnosed with HIV infection for 16 years with no previous AIDS-defining diagnoses or other complications. A self-imposed, four-year treatment interruption and multiple failures of contemporary HIV treatment regimens, due to medication intolerance, led to restarting a previous effective regimen of didanosine, lamivudine, and boosted indinavir six months prior to admission. Her viral load one month prior to admission was non-detectable (<50 copies/mL) and CD4 count was 381. For 5 months prior to admission, she had intermittently complained of low-grade fevers, low back pain along with other arthralgias and myalgias, night sweats, fatigue, and hair loss. Evaluation during this time, including comprehensive metabolic panel, CBC, TSH, serology for coccidioidomycosis, RPR, pregnancy test, and CXR, were unremarkable. Three days prior to admission she was noted to have an elevated erythrocyte sedimentation rate of 69 mm/hr (normal range, 0-20 mm/hr) and C-reactive protein of 4.93 mg/dL (normal, 0-0.5 mg/dL) with a negative rheumatoid factor and ANA. Serum bicarbonate level was 21 mmol/L (normal, 22-29 mmol/L) and lactic acid level was 2.2 mmol/L (normal, 0.5-2.2 mmol/L) Her past medical history was significant for childhood repair of a patent ductus arteriosis and depression. She worked as a warehouse clerk, denied tobacco or alcohol use, and always used condoms during intercourse. She lived in Arizona for 20 years and resided with her HIV-infected fiancé, daughter, and granddaughter. She was involved with animal husbandry and lived in the suburbs with five dogs and six horses. Physical Exam: On admission she appeared well. The weight was 46.3 kg, the height 142 cm, the blood pressure 165/60, the pulse 103, and the temperature 39.4° C. Her physical examination revealed no abnormalities. Initial test results: Comprehensive metabolic panel (other than a serum bicarbonate level of 21), CBC, routine blood cultures, serology for Epstein-Barr virus, and stool studies, were unrevealing. Differential Diagnosis: • Drug reaction: Multiple non-specific constitutional symptoms have been reported with most antiretrovirals. Nucleoside analogs have been associated with lactic acidosis and steatohepatosis. While she did not have elevated transaminases, the borderline lactic acidosis was of concern. • Fungal infection: Coccidioidomysosis (cocci) is frequently in the differential diagnosis of febrile illnesses in central and southern Arizona. Seen mostly in recent arrivals to the area, it presents mostly with pulmonary and non-specific viral-like symptoms. Disseminated cocci is always a concern in HIV-infected individuals in the area, but was felt unlikely given her CD4 count and negative serology. Cryptococcus neoformans can present with only unexplained fevers and malaise. There was no history of travel to areas endemic for histoplasmosis. Standard serologic testing was done to rule out fungal infection, despite a low index of suspicion. • Bacterial: Disseminated Mycobacterium tuberculosis and Mycobacterium avium seemed unlikely given her CD4 count and normal CXR. Salmonella infections in HIV-infected patients may present more frequently with bacteremia and may have a paucity of gastrointestinal manifestations.(1) • Viral: Systemic viral infections such as Epstein-Barr virus and parvovirus B19 were considered less likely given the duration of her symptoms. • Zoonotic diseases: Brucella melitensis presents with a clinical picture consistent with that of our patient, however there was no exposure to goats, livestock, or unpasteurized milk. Ehrlichiosis, Campylobacter, Giardia, Listeriosis, Q fever, Rhodococcus equi all could be carried by a dog or horse