Chronic Q Fever in the United States

Abstract

Infections due to Coxiella burnetii, the causative agent of Q fever, are uncommon in the United States. Cases of chronic Q fever are extremely rare and most often manifest as culture-negative endocarditis in patients with underlying valvular heart disease. We describe a 31-year-old farmer from West Virginia with a history of congenital heart disease and recurrent fevers for 14 months who was diagnosed with Q fever endocarditis based on an extremely high antibody titer against Coxiella burnetii phase I antigen. Despite treatment with doxycycline, he continued to have markedly elevated Coxiella burnetii phase I antibody titers for 10 years after the initial diagnosis. To our knowledge, this case represents the longest follow-up period for a patient with chronic Q fever in the United States. We review all cases of chronic Q fever reported in the United States and discuss important issues pertaining to epidemiology, diagnosis, and management of this disease. CASE REPORTA 31-year-old farmer from West Virginia was admitted in June 1995 because of recurrent episodes of fever as high as 39°C, night sweats, paroxysmal coughing, chest pressure, decreased appetite, fatigue, and an 11-kg involuntary weight loss over the preceding 14 months. He had been treated several times for presumed bronchitis with various antibiotics, but his complaints had worsened since December 1994. His past medical history was significant for congenital heart disease, including dextrocardia, a double-outlet right ventricle, a ventricular septal defect, and severe pulmonary stenosis. As an infant, he had undergone operative placement of a right Blalock-Taussig shunt, and at age 12, he underwent surgery for closure of a ventricular septal defect and placement of a conduit between the right ventricle and pulmonary artery. At age 26, he underwent surgery for replacement with a 22-mm Hancock conduit. He participated in birthing his calves, one of which was stillborn around the time of the onset of his illness. He was treated empirically with penicillin, gentamicin, and vancomycin, and his fevers resolved.On physical examination, he was a thin, chronically ill-appearing white male. His vital signs were within normal limits, and he was afebrile. Cardiac examination revealed a grade 3/6 harsh systolic ejection murmur heard maximally at the right upper sternal border without radiation. The chest examination was normal. There was no hepatosplenomegaly, enlarged lymph nodes, or peripheral stigmata of endocarditis. Laboratory studies revealed the following results: hematocrit level was 41%; white blood cell count was 7.3 ϫ 10 9 white blood cells/ liter, with a differential cell count of 35% segmented neutrophils, 5% bands, and 54% lymphocytes; platelets were aggregated and uncountable; electrolyte panel and urinalysis were normal; erythrocyte sedimentation rate was 34 mm/h; and alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase levels were elevated at 198 U/liter, 244 U/ liter, and 196 U/liter, respectively. Serologies for hepatiti...

AttenuatedCoxiella burnetiiPhase II Causes a Febrile Response in Gamma Interferon Knockout and Toll-Like Receptor 2 Knockout Mice and Protects against Reinfection

“…In the United States, sero-epidemiologic studies suggest that C. burnetii infections have increased in cattle in the last decades; however, the number of reported human infections remains low (21). From 1948 through 1999, 436 cases of Q fever were reported in the United States, with an average of 20 cases annually.…”

<b><i>Coxiella burnetii</i></b> - Pathogenic Agent of Q (Query) Fever

“…The bacterial load rapidly decreases if doxycycline and chloroquine are administered. If antibiotic treatment is transiently interrupted, Coxiella resistant strains are selected within 3 years and lead to relapses of endocarditis [45,46]. Coxiella survives for years in granulomas which are formed in various organs, not only restricted to heart and cardiac valves tissues [46].…”

Maladies émergentes transmises par les tiques

“…Moins souvent, la fièvre Q peut induire une hépatite granulomateuse avec malaises, fièvre, douleur abdominale et jaunisse. L'endocardite [61] est une complication tardive de la fièvre Q, pouvant survenir des mois ou des années après l'infection, et pouvant avoir un taux de mortalité d'environ 10%, même chez les patients traités.…”