scholarly journals Predominant Immunoglobulin A Response to Phase II Antigen of Coxiella burnetii in Acute Q Fever

1999 ◽  
Vol 6 (2) ◽  
pp. 173-177 ◽  
Author(s):  
Pierre-Edouard Fournier ◽  
Didier Raoult

ABSTRACT Diagnosis of acute Q fever is usually confirmed by serology, on the basis of anti-phase II antigen immunoglobulin M (IgM) titers of ≥1:50 and IgG titers of ≥1:200. Phase I antibodies, especially IgG and IgA, are predominant in chronic forms of the disease. However, between January 1982 and June 1998, we observed anti-phase II antigen IgA titers of ≥1:200 as the sole or main antibody response in 10 of 1,034 (0.96%) patients with acute Q fever for whom information was available. In order to determine whether specific epidemiological or clinical factors were associated with these serological profiles, we conducted a retrospective case-control study that included completion of a standardized questionnaire, which was given to 40 matched controls who also suffered from acute Q fever. The mean age of patients with elevated phase II IgA titers was significantly higher than that usually observed for patients with acute Q fever (P = 0.026); the patients were also more likely than controls to live in rural areas (P = 0.026) and to have increased levels of transaminase in blood (P = 0.03). Elevated IgA titers are usually associated with chronic Q fever and are directed mainly at phase I antigens. Although the significance of our findings is unexplained, we herein emphasize the fact that IgA antibodies are not specific for chronic forms of Q fever and that they may occasionally be observed in patients with acute disease. Moreover, as such antibody profiles may not be determined by most laboratories, which test only for total antibody titers to phase I and II antigens, the three isotype-specific Ig titers should be determined as the first step in diagnosing Q fever.

2012 ◽  
Vol 19 (10) ◽  
pp. 1661-1666 ◽  
Author(s):  
C. C. H. Wielders ◽  
L. M. Kampschreur ◽  
P. M. Schneeberger ◽  
M. M. Jager ◽  
A. I. M. Hoepelman ◽  
...  

ABSTRACTLittle is known about the effect of timing of antibiotic treatment on development of IgG antibodies following acute Q fever. We studied IgG antibody responses in symptomatic patients diagnosed either before or during development of the serologic response toCoxiella burnetii. Between 15 and 31 May 2009, 186 patients presented with acute Q fever, of which 181 were included in this retrospective study: 91 early-diagnosed (ED) acute Q fever patients, defined as negative IgM phase II enzyme-linked immunosorbent assay (ELISA) and positive PCR, and 90 late-diagnosed (LD) acute Q fever patients, defined as positive/dubious IgM phase II ELISA and positive immunofluorescence assay (IFA). Follow-up serology at 3, 6, and 12 months was performed using IFA (IgG phase I and II). High IgG antibody titers were defined as IgG phase II titers of ≥1:1,024 together with IgG phase I titers of ≥1:256. At 12 months, 28.6% of ED patients and 19.5% of LD patients had high IgG antibody titers (P= 0.17). No statistically significant differences were found in frequencies of IgG phase I and IgG phase II antibody titers at all follow-up appointments for adequately and inadequately treated patients overall, as well as for ED and LD patients analyzed separately. Additionally, no significant difference was found in frequencies of high antibody titers and between early (treatment started within 7 days after seeking medical attention) and late timing of treatment. This study indicates that early diagnosis and antibiotic treatment of acute Q fever do not prohibit development of the IgG antibody response.


1990 ◽  
Vol 36 (4) ◽  
pp. 292-296 ◽  
Author(s):  
J. Embil ◽  
J. C. Williams ◽  
T. J. Marrie

The isotypic immune response of 16 individuals who developed Q fever pneumonia following exposure to an infected parturient cat was studied. The enzyme-linked immunosorbent (ELISA) test was used to detect IgM, IgA, and IgG antibodies to phase I and phase II Coxiella burnetii whole-cell antigens and to the phase I lipopolysaccharide. The indirect immunofluorescent antibody (IFA) test was also used to detect antibodies to phase I and phase II whole cells. None of the 16 subjects developed antibodies to the phase I lipopoly saccharide. The ELISA was more sensitive than the IFA test. IgM antibodies to phase II antigen were detectable by ELISA in 80% of the subjects at the time of onset of symptoms and were still present in 7 of the 8 tested at 32 weeks following the onset of symptoms. In all instances (ELISA: IgG, IgM; IFA: IgG, IgM) phase II antibodies developed earlier and reached higher levels than did phase I antibodies. The absence of antibodies to phase I lipopolysaccharide in acute Q fever combined with our unpublished findings of antibodies to phase I lipopoly saccharide in chronic Q fever suggests that this test may be used to distinguish acute from chronic Q fever. Key words: Q fever, immune response, ELISA.


Author(s):  
Paulo Sérgio Gonçalves da Costa ◽  
Marco Emilio Brigatte ◽  
Dirceu Bartolomeu Greco

Q fever has been considered non-existing in Brazil where reports of clinical cases still cannot be found. This case-series of 16 patients is a result of a systematic search for such illness by means of clinical and serologic criteria. Serologic testing was performed by the indirect microimmunofluorescence technique using phase I/II C. burnetii antigens. Influenza-like syndrome was the most frequent clinical form (eight cases - 50%), followed by pneumonia, FUO (fever of unknown origin), mono-like syndrome (two cases - 12.5% each), lymphadenitis (one case - 6.3%) and spondylodiscitis associated with osteomyelitis (one case - 6.3%). The ages varied from four to 67 years old with a median of 43.5. All but one patient had positive serologic tests for phase II IgG whether or not associated with IgM positivity compatible with acute infection. One patient had both phase I and phase II IgG antibodies compatible with chronic Q fever. Seroconvertion was detected in 10 patients. Despite the known limitations of serologic diagnosis, the cases here reported should encourage Brazilian doctors to include Q fever as an indigenous cause of febrile illness.


1996 ◽  
Vol 7 (1) ◽  
pp. 45-48
Author(s):  
TJ Marrie ◽  
Linda Yates

Western immunoblotting was used to compare the immune response toCoxiella burnetiiphase I and phase II antigens of humans with acute and chronic Q fever with that of infected cats, rabbits, cows and raccoons. The cats, rabbits, cows and raccoons had an immunoblot profile similar to that of the human with chronic Q fever.


2012 ◽  
Vol 140 (11) ◽  
pp. 1950-1954 ◽  
Author(s):  
C. F. H. RAVEN ◽  
J. L. A. HAUTVAST ◽  
T. HERREMANS ◽  
A. C. A. P. LEENDERS ◽  
P. M. SCHNEEBERGER

SUMMARYWe investigated the positive predictive value (PPV) of a solitary positive immunoglobulin M (IgM) phase II response for the serodiagnosis of acute Q fever detected with either an indirect immunofluorescence assay (IFA) or an enzyme-linked immunosorbent assay (ELISA). Initial and follow-up sera from patients suspected of acute Q fever were included if initially only IgM phase II tested positive with IFA in 2008 (n=92), or ELISA in 2009 (n=85). A seroconversion for Q fever was defined as an initial sample being IgG phase II negative but positive in the follow-up sample. The PPV of an initial isolated IgM phase II result detected by IFA or ELISA was 65% and 51%, respectively, and therefore appeared not to adequately predict acute Q fever. For this reason it cannot be used as a diagnostic criterion nor should it be included in public health notification without confirmation with other markers or a follow-up serum sample.


1999 ◽  
Vol 12 (4) ◽  
pp. 518-553 ◽  
Author(s):  
M. Maurin ◽  
D. Raoult

SUMMARY Q fever is a zoonosis with a worldwide distribution with the exception of New Zealand. The disease is caused by Coxiella burnetii, a strictly intracellular, gram-negative bacterium. Many species of mammals, birds, and ticks are reservoirs of C. burnetii in nature. C. burnetii infection is most often latent in animals, with persistent shedding of bacteria into the environment. However, in females intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being released per gram of placenta. Humans are usually infected by contaminated aerosols from domestic animals, particularly after contact with parturient females and their birth products. Although often asymptomatic, Q fever may manifest in humans as an acute disease (mainly as a self-limited febrile illness, pneumonia, or hepatitis) or as a chronic disease (mainly endocarditis), especially in patients with previous valvulopathy and to a lesser extent in immunocompromised hosts and in pregnant women. Specific diagnosis of Q fever remains based upon serology. Immunoglobulin M (IgM) and IgG antiphase II antibodies are detected 2 to 3 weeks after infection with C. burnetii, whereas the presence of IgG antiphase I C. burnetii antibodies at titers of ≥1:800 by microimmunofluorescence is indicative of chronic Q fever. The tetracyclines are still considered the mainstay of antibiotic therapy of acute Q fever, whereas antibiotic combinations administered over prolonged periods are necessary to prevent relapses in Q fever endocarditis patients. Although the protective role of Q fever vaccination with whole-cell extracts has been established, the population which should be primarily vaccinated remains to be clearly identified. Vaccination should probably be considered in the population at high risk for Q fever endocarditis.


2015 ◽  
Vol 16 (6) ◽  
pp. 958-961 ◽  
Author(s):  
Salim Mattar V ◽  
Verónica Contreras C ◽  
Marco Gonzalez T ◽  
Francisco Camargo ◽  
Jaime Alvarez ◽  
...  

<p>Q fever is a zoonosis caused by <em>Coxiella burnetii</em>. In Colombia, there have been very few human cases reported to date. This report describes the case of a 56-year-old patient with a background in agriculture and livestock handling. An indirect immunofluorescence assay (IFA) showed high titers of IgG for <em>C. burnetii</em> anti-phase I (1: 256) and anti-phase II (1:1024). For the next six months the patient’s IgG antibody titers remained high, and, after treatment with doxycycline, the IgG antibody titers decreased to 50 % (anti-phase I 1:128 and anti-phase II 1:512); this profile suggests an infection of <em>C. burnetii</em>.</p>


2009 ◽  
Vol 17 (2) ◽  
pp. 286-290 ◽  
Author(s):  
Peter M. Schneeberger ◽  
Mirjam H. A. Hermans ◽  
Erik J. van Hannen ◽  
Jeroen J. A. Schellekens ◽  
Alexander C. A. P. Leenders ◽  
...  

ABSTRACT The world's largest Q fever outbreak is ongoing in The Netherlands with around 3,000 confirmed cases since the first half of 2007. Increased awareness has resulted in early referral of patients for diagnostics. An important drawback to serological diagnosis of acute Q fever is the lag phase in antibody response. Therefore, we evaluated the performance of a real-time PCR for detection of Coxiella burnetii DNA using serum samples from patients with acute Q fever. PCR, targeting IS1111, was retrospectively performed on acute-phase and follow-up convalescent-phase serum samples from 65 patients with acute Q fever as diagnosed by immunofluorescence assay. The results obtained by PCR were related to disease stage as defined by subsequent appearance of phase II IgM, phase II IgG, phase I IgM, and phase I IgG (IgM-II, IgG-II, IgM-I, and IgG-I, respectively) antibodies and time since onset of disease. In addition, we analyzed seronegative acute-phase serum samples from patients with inconclusive Q fever serology, because no convalescent-phase serum samples were available. PCR was scored positive in 49/50 (98%) seronegative sera, 9/10 (90%) sera with isolated IgM-II antibodies, 3/13 (23%) sera with IgM-II/IgG-II antibodies, 2/41 (5%) sera with IgM-II/IgG-II/IgM-I antibodies, 0/15 (0%) sera with IgM-II/IgG-II/IgM-I/IgG-I antibodies, and 0/1 (0%) serum sample with IgM-II/IgG-II/IgG-I antibodies. The latest time point after onset of disease in which C. burnetii DNA could be detected was at day 17. In patients with inconclusive Q fever serology, PCR was positive in 5/50 (10%) cases. We conclude that real-time PCR with serum samples is indispensable for early diagnosis of acute Q fever. C. burnetii DNA becomes undetectable in serum as the serological response develops.


2005 ◽  
Vol 49 (7) ◽  
pp. 2673-2676 ◽  
Author(s):  
Jean-Marc Rolain ◽  
Areen Boulos ◽  
Marie-Noëlle Mallet ◽  
Didier Raoult

ABSTRACT Endocarditis is the major clinical manifestation of chronic Q fever. Although doxycycline along with hydroxychloroquine remains the mainstay of medical therapy for Q fever endocarditis, there are wide variations in the rapidity of the patient's decline of antibody levels during such therapy. We undertook a retrospective examination of whether there was any correlation between the ratio of serum concentration to MIC of doxycycline and response to treatment in patients with Q fever endocarditis. Included herein are 16 patients from whom Coxiella burnetii was isolated from cardiac valve materials. Serology and measurement of doxycycline and hydroxychloroquine serum levels were performed and recorded after 1 year of treatment. The MIC of doxycycline for C. burnetii isolates was determined using the shell vial assay in a real-time quantitative PCR assay. At the completion of a yearlong therapy with doxycycline-hydroxychloroquine, all those that showed a low decline of antibody levels (n = 6) (i.e., <2-fold decrease in antibody titer to phase I C. burnetii antigen) had a ratio of serum doxycycline concentration to MIC between 0.5 and 1. In contrast, those having a ratio of ≥1 showed a rapid decline of phase I antibody levels (n = 9; P < 0.05). The only patient who died had a serum doxycycline-to-MIC ratio of <0.5, and the isolate of C. burnetii cultured from this patient was resistant to doxycycline (MIC = 8 μg/ml). The ratio of serum doxycycline concentration to MIC should be monitored during the course of therapy in patients with Q fever endocarditis.


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