Bartonella quintana Aortitis in a Man with AIDS, Diagnosed by Needle Biopsy and 16S rRNA Gene Amplification

Abstract

A man with newly diagnosed AIDS presented with months of back pain and fever. Computed tomography (CT) results demonstrated aortitis with periaortic tissue thickening. DNA amplification of biopsy tissue revealed Bartonella quintana, and Bartonella serologies were subsequently noted to be positive. The patient improved with prolonged doxycycline and rifabutin treatment. This case illustrates how molecular techniques are increasingly important in diagnosing Bartonella infections. CASE REPORTA 48-year-old heterosexual African male with type II diabetes presented to an emergency room (ER) with several months of abdominal pain, back pain, polydipsia, loss of 30 pounds of body weight, and subjective fevers. He was febrile (38.6°C) and tachycardic, with a glucose level of 298 mg/dl. He was given intravenous fluids and metformin and discharged from the ER. Subsequently, his HIV-1 test returned a positive result; his CD4 ϩ T cell count was 68 cells/mm 3 (7%), and his HIV-1 RNA level was 537,519 copies/ ml. He was empirically started on antiretroviral therapy and prophylactic trimethoprim-sulfamethoxazole. Four weeks later, the patient described persistent abdominal and back pain, fever, and chills. The mid-thoracic back pain was sharp, constant, and relieved by leaning forward.The patient worked as a taxi driver, lived alone in an apartment, and had no pets. He grew up in Ethiopia and moved to the United States in 1991. He reported being heterosexual and denied contact with commercial sex workers or having surgeries or tattoos. He reported no alcohol, tobacco, or illicit drug use. He had last traveled to Ethiopia in 2006, stayed in rural areas with goats, sheep, cows, dogs, and cats, and consumed only store-bought milk and meat.On examination, the patient had no thrush or lymphadenopathy. His abdomen was soft and mildly tender in response to palpation throughout, without rebound. There was no tenderness in response to palpation along the spine. He had no cutaneous lesions. His laboratory results were notable for a white blood cell count of 2.9 ϫ 10 3 /l, with 38% polymorphonuclear cells, 36% lymphocytes, 8% monocytes, 15% eosinophils, and a hemoglobin level of 8.9 g/dl. His liver function test results were normal.Single-phase phase-contrast-enhanced CT results demonstrated abnormal circumferential soft tissue thickening involving the lower abdominal aorta, with additional periaortic soft tissue, inseparable from the aortic wall. Heterogeneous enhancement within the soft tissue suggested active inflammation. A subsequent multiphase CT angiography (CTA) procedure confirmed aortic wall thickening, extending from the superior mesenteric artery to the proximal left common iliac artery (Fig. 1A). Additionally, a wedge-shaped hypodense region in the posterior left kidney was suspicious for a small infarct.The patient was hospitalized for further evaluation. Routine bacterial, mycobacterial, and fungal blood culture results were negative, as were those of Coccidioides complement fixation and immunodiffusion assays, Cryptococcus ...

Bartonella infections in cats and dogs including zoonotic aspects

“…Specialized culture techniques including lysis centrifugation, cell culture isolation and growth enrichment in insect biochemical composition growth media are the “gold standard” for confirmation of Bartonella infection. Optimal samples for microbiological culture include blood, cerebrospinal fluid [ 138 ], joint fluid [ 81 ], pathological effusions [ 138 ] and tissue biopsies [ 139 ]. In reservoir-adapted hosts such as rodents and cats and infrequently in accidental hosts (sick dogs or humans), Bartonella spp.…”

Microbial Identification Using DNA Target Amplification and Sequencing: Clinical Utility and Impact on Patient Management

“…PCR testing was performed at the University of Washington Molecular Diagnostic Laboratory, with samples sent for bacterial, fungal, and/or mycobacterial testing using methods previously described [ 12 , 22 , 35–40 ]. Broad-range bacterial PCR targeted the 16S rRNA (forward primer 27F sequence, 5’-AGAGTTTGATCCTGGCTCAG-3’; reverse primer 357-mL sequence, 5’-CTGCTGCCICCCGTAGGAG-3’) [ 35 ].…”

Tropheryma whipplei infection (Whipple's disease) in a patient after liver transplantation

“…The primer sets used have a detection limit on fresh tissue of 100 and 5 copies respectively. Broad‐range bacterial PCR of a 263 base‐pair segment of the 16S ribosomal RNA gene described previously also failed to amplify. Immunohistochemical staining for T. whipplei was equivocal.…”