1/13. q fever endocarditis: diagnostic approaches and monitoring of therapeutic effects.The scope of current diagnostic methods for q fever endocarditis includes serology, direct demonstration of coxiella burnetii in the resected heart valve tissue, and animal inoculation studies. Illustrated by a clinical case report, the different methods are presented and discussed. serology represents the primary method, using the techniques of complement fixation, indirect immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). The latter two techniques allow the detection of immunoglobulins G, M, and A to the phase I and II antigens of C. burnetii. After cardiac surgery, we visualized C. burnetii on smears and specifically stained it on histologic sections of the resected heart valve by light and electron microscopic immunohistochemistry. In addition, seroconversion in animals after inoculation with valve specimens confirmed the presence of C. burnetii in the heart valve. The antibody titers determined by ELISA correlated well with the patient's clinical course during the treatment period. Therefore it is suggested that its usefulness for monitoring the efficacy of antimicrobial agents in patients with q fever endocarditis should be further evaluated.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/13. Concomitant or consecutive infection with coxiella burnetii and tickborne diseases.BACKGROUND: q fever is a worldwide zoonosis caused by coxiella burnetii, which can be isolated from ticks. Reports of people with both q fever and other tickborne diseases are rare. In this study, we describe 6 patients with q fever who were infected with 1 of the following tickborne pathogens: rickettsia conorii (2 patients), Rickettsia slovaca (2), Rickettsia africae (1), and francisella tularensis (1). methods: Diagnoses were made on the basis of results of microimmunofluorescence assays for detection of C. burnetii, R. conorii, R. slovaca, R. africae, and F. tularensis antigens. Cross-adsorption studies and Western blots were used to confirm dual infections. RESULTS: Among the 6 cases presented, 3 were probably due to a concomitant infection after a tick bite, whereas the remaining 3 were more likely consecutive infections. CONCLUSIONS: Because acute q fever is often asymptomatic, we recommend that patients infected with the tickborne pathogens mentioned above also undergo routine testing for concurrent infections with C. burnetii.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/13. Chronic q fever in the united states.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.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/13. q fever in the Southern california desert: epidemiology, clinical presentation and treatment.Despite the absence of a natural reservoir for q fever in the desert of Southern california, six cases have been identified during the past 32 years. During that period of time, two areas have been used by northern sheep ranchers from idaho and wyoming to import sheep to an area in the Coachella Valley through 1985. Thereafter, because of housing development, the sheep area was moved to Blythe along the colorado River. All but two of these patients probably acquired infection by coxiella burnetii by living or working in close proximity to these grazing areas but not directly involved with the sheep. The shift of infected patients from the Coachella Valley to Blythe (100 miles distant) seems to support that supposition. All patients with acute q fever developed antibodies primarily to phase II antigen, whereas the only person with chronic q fever developed phase I antibodies. All patients presented with granulomatous hepatitis. One also had a pulmonary infiltrate, and the single individual with chronic q fever also had a mitral valve prosthesis, although echocardiography could not define endocarditis. All patients with acute infections responded to 3-5 weeks of therapy with doxycycline, whereas the patient with chronic disease failed 3 years of therapy with combination regimens. Further studies at the Eisenhower Medical Center on the prevalence of infection in Blythe, CA, and elsewhere are anticipated.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/13. Truckin' pneumonia--an outbreak of q fever in a truck repair plant probably due to aerosols from clothing contaminated by contact with newborn kittens.We describe an outbreak of q fever affecting 16 of 32 employees at a truck repair plant. None of the cases were exposed to cattle, sheep or goats, the traditional reservoirs of q fever. The cases did not work, live on, or visit farms or attend livestock auctions. One of the employees had a cat which gave birth to kittens 2 weeks prior to the first case of q fever in the plant. The cat owner fed the kittens every day before coming to work as the cat would not let the kittens suckle. serum from the cat had high antibody titres to phase I and phase II coxiella burnetii antigens. The attack rate among the employees where the cat owner worked, 13 of 19 (68%), was higher than that of employees elsewhere, 3 of 13 (28%) [P less than 0.01]. The cat owner's wife and son also developed q fever. None of the family members of the other employees with q fever was so affected. We conclude that this outbreak of q fever probably resulted from exposure to the contaminated clothing of the cat owner.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/13. Acute heart failure due to q fever endocarditis.We report a case of q fever endocarditis in a patient who presented with a slight pyrexia and acute cardiac failure due to aortic incompetence. The diagnosis was made by detecting high titres of serum IgG and IgA antibody against coxiella burnetii phase I antigens and confirmed by demonstrating C. burnetii on the excised aortic valve using immunofluorescence and electron microscopy. aortic valve replacement was followed by initially successful antibiotic treatment for 15 months. Reappearance of IgA anti-phase I antibodies 5 months later suggested continued presence of bacteria, although the patient's condition remained satisfactory. In endemic areas, such as rural southern france, q fever endocarditis should be considered when there is evidence of acute heart valve damage but are few other features of infection.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/13. Glomerular nephropathy associated with chronic q fever.Of three patients with coxiella burnetii endocarditis, two developed focal segmental proliferative glomerulonephritis (GN), and the third developed diffuse intracapillary proliferative glomerulonephritis. In one case, a good therapeutic response was followed by partial remission of the renal alterations, but 10 months later there were clinical and histological signs of active glomerular nephropathy, suggesting that the antigenic stimulus persisted. In another case, poor evolution of the infection was accompanied by clinically and histologically aggressive glomerular nephropathy, and advanced renal failure. The third patient, who had diffuse proliferative glomerulonephritis, underwent renal biopsy earlier than the other two cases, and the behavior of the nephropathy has not been aggressive to date. Immunohistopathologic study revealed a diffuse granular deposit of IgM and C3 in all three cases; the first two also presented a discrete linear IgG deposit in the capillary loops. Attempts to identify C burnetii antigen at the glomerular level by immunohistologic techniques failed in two patients. The literature on the association of chronic q fever with glomerulonephritis is briefly reviewed.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
8/13. q fever endocarditis: relapse five years after successful valve replacement for a first unrecognized episode.A 59-yr-old man presented with mitral endocarditis and negative blood cultures. antibodies to phase 2 and phase 1 antigens of Coxiella burneti were detected and a diagnosis of q fever endocarditis was made. Five years earlier, this patient had been successfully treated by aortic valve replacement for a first episode of endocarditis with negative blood cultures. Giemsa and Machiavello stains of the native aortic valve were made retrospectively and showed coccobacilli highly suggestive of Coxiella organisms. It is concluded that the first episode was q fever endocarditis and that the failure to recognize this aetiology at that time, and the absence of adequate medical therapy, is the cause of the present episode.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/13. Immunoenzymatic test for Q-fever.An immunoenzymatic test using as antigen purified suspensions of Coxiella burnetti coated by methylglyoxal on microtiter plates was developed. Multiple testing of the same sera gave similar results: two dilutions of serum (1:400 and 1:1600) were used in routine tests. Good agreement between the immunoenzymatic and the indirect immunofluorescent antibody tests was obtained for 41 of 50 sera examined. Five sera negative by the immunofluorescent antibody test were positive by the immunoenzymatic test; this result may be due to the higher sensitivity of the latter test. On the other hand, three sera with higher titers by the indirect immunofluorescent antibody test showed a rather feeble positivity by the immunoenzymatic test. This is probably due to the different specificity of the reacting antibodies in the two methods. The indirect immunofluorescent antibody test permits better distinction of the very high titers (greater than 1:5120) than the immunoenzymatic test. The immunoenzymatic test seems to be the method of choice for seroepidemiology surveys of Q-fever; however, its use for clinical serodiagnosis needs further confirmation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/13. The pathology of q fever hepatitis. A case diagnosed by liver biopsy.A 52-year-old woman with fever and low grade hepatitis had q fever, a diagnosis made by the characteristic granulomas, containing fibrin and vacuoles, on liver biopsy and confirmed by serology. fibrin was demonstrated in the granulomas but coxiella burnetii antigens were not. The literature on the histopathology of the liver in both acute q fever and q fever endocarditis shows that none of the 220 cases of q fever endocarditis, with one possible exception, had the characteristic granulomas of acute q fever. Rather they displayed a range from normality through nonspecific reactive hepatitis to occasional nonspecific granulomas. Thus, the characteristic granulomas of acute q fever appear to be transient even if active infection persists. The definition of chronic q fever should have a temporal characteristic rather than a serologic one.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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