Conditions affecting the viability of spheroplasts in urine

Penicillin-induced spheroplasts from Escherichia coli and Proteus vulgaris, which at neutral pH had little resistance to osmotic lysis, retained viability in media of low osmolality at pH 5.0 to 5.5. In the presence of 1,000 IU of penicillin per ml (pH 5.0) in liquid media, E. coli remained in rod form without conspicuous growth. On hypotonic agar media at pH 5.2 with 1,000 IU of penicillin per ml, the bacteria grew out as L-type colonies. These findings are discussed in relation to penicillin therapy.

Antibodies to Chlamydia pneumoniae in young Swedish orienteers

During 1992-93 sera from 1790 Swedish elite orienteers were tested for antibodies to Chlamydia pneumoniae. The reason for this was that a cluster of 16 cases of sudden unexpected cardiac death had occurred among Swedish orienteers and DNA from C. pneumoniae had been found in the myocarditic heart and in the lung in 1 of 2 deceased athletes in whom testing was feasible; in addition, C. pneumoniae IgG was found in all 5 cases where serum was available. Among the orienteers, the prevalence rates of IgG antibodies in males and females were 54% (n = 1194) and 50% (n = 596), respectively. The corresponding figures for 319 male and female blood donors were 60% (n = 169) and 53% (n = 150), respectively. These differences are not statistically significant. Male orienteers had a lower prevalence of IgA antibodies than male blood donors (19% and 26%, respectively; p < 0.05), while no such difference was found in females (16% and 18%). The prevalence of IgM antibodies was < 1% in all groups. Neither the performance level of the orienteers nor the place of residence affected the antibody prevalence. In conclusion, Swedish orienteers do not show a higher prevalence of antibodies to C. pneumoniae than healthy blood donors.

An association between chronic infection with Chlamydia pneumoniae and lung cancer. A prospective 2-year study

This study assesses a possible relationship between chronic Chlamydia pneumoniae (Cpn) infection and lung cancer (LC). A total of 210 consecutive patients (136 M, 74 F) were diagnosed with LC during a 2-year period. Blood was obtained from 128 M and 70 F patients for Cpn serology. Repeat blood specimens were taken after 3 months. Throat specimens for Cpn DNA analysis by PCR were taken from 110/136 M and 63/74 F Seventy-four cytobrush specimens were taken and also analyzed by polymerase chain reaction (PCR). Fifty (29 M, 21 F) bronchial biopsies and 8 (6 M, 2 F) tumors resected at surgery were analyzed for Cpn by immunohistochemistry (IHC). Males had significantly more often squamous-cell carcinoma (SCC) than females. Other types of LC were more equally distributed between males and females. The difference between males and females regarding smoking history was significant, and male LC patients had significantly higher levels of IgG and/or IgA antibodies than female LC patients. Male and female LC patients had significantly higher prevalences of high antibody titers than controls. A high prevalence of unusually high titers of specific Cpn antibodies was found in male LC patients. This could indicate that LC may be induced by chronic Cpn infection, since stable high titers of Cpn antibodies, especially IgA, are a hallmark of chronic infections.

Demonstration of Chlamydia pneumoniae in the adenoid from children with and without secretory otitis media using immunohistochemistry and PCR

Chlamydia pneumoniae has been found in patients with middle ear inflammation. The adenoid, which has a central role in the development of secretory otitis media (SOM), may act as a reservoir for bacteria causing ear infection. Adenoid tissue was examined for the presence of C. pneumoniae. Twenty children undergoing adenoidectomy because of hyperplastic adenoids, 10 with SOM and 10 without SOM, were examined with nasopharyngeal swabs for routine bacteriological culture, serology for C. pneumoniae and throat swabs for C. pneumoniae PCR. The removed tissues were analyzed for C. pneumoniae using immunohistochemical (IHC) analysis and PCR. In the group of children with SOM samples were also taken from the middle ear fluid for routine bacteriological culture and PCR for C. pneumoniae. C. pneumoniae was found in the adenoid by PCR in 3 cases from each group and from all 20 children by IHC. Four children in each group had increased levels of specific antibodies to C. pneumoniae. Two children with SOM had high antibody titers and a positive PCR from a throat swab. Two children were PCR-positive for C. pneumoniae in fluid from the middle ear. The significance of these findings is not yet clear.

Chlamydia pneumoniae in children undergoing adenoidectomy

Chlamydia pneumoniae is a common respiratory pathogen which is often found in paediatric populations. Little is known about the true colonization rate and the localization of the bacteria in the respiratory tract. In this study, immunohistochemistry was used to examine adenoids from 69 children undergoing elective adenoidectomy. Throat swabs for polymerase chain reaction (PCR) and blood samples for serology were also obtained. Chlamydia pneumoniae was demonstrated in the adenoids by immunohistochemistry in 68 of the children. Five children (7%) had a positive C. pneumoniae PCR test from throat swabs and 14 children (20%) had detectable antibodies by the microimmunofluorescence technique.

CONCLUSION

The results suggest that C. pneumoniae is a common finding in the adenoids of children undergoing adenoidectomy. Whether or not C. pneumoniae plays a pathogenic role in this patient population could not be determined from the data obtained in this investigation.

Seroprevalence of antibodies to Chlamydia pneumoniae in elderly people: a two-decade longitudinal and cohort difference study

A gerontological population of 178 men and 249 women was investigated regarding the prevalence of antibodies specific to Chlamydia pneumoniae. A longitudinal substudy was carried out on 22 men and 44 women, age range 70-90 y. Antibodies specific to C. pneumoniae were common. Men had higher prevalences and higher antibody levels than women. More than half of the individuals in the longitudinal study had significant IgG and/or IgA titre changes (> or = 4-fold) between the ages of 70 and 90 y, suggesting that C. pneumoniae infections are common in the elderly population. This is of importance for the treatment of respiratory infections in elderly people.

Chlamydia pneumoniae seropositivity is associated with carotid artery intima-media thickness

BACKGROUND AND PURPOSE

Infection may both augment the atherosclerotic process and contribute to later manifestations of overt clinical disease. Chlamydia pneumoniae elementary bodies have been detected in atherosclerotic lesions. The aim of the present study was to investigate whether elevated titers of antibodies and circulating immune complexes to C pneumoniae were associated with ultrasound findings indicating presence of atherosclerosis in the carotid artery.

METHODS

Serum titers of antibodies to C pneumoniae (IgM, IgA, IgG, and circulating immune complex) were related to intima-media thickness (IMT) and plaque status measured by B-mode ultrasound in the carotid artery in 113 men with treated hypertension and at least 1 of the following risk factors: hypercholesterolemia, smoking, or diabetes.

RESULTS

Any of the titers was elevated in 56 (50%) men, and common carotid artery IMT was thicker in this group compared with the 57 men without any elevated titers (1.00 versus 0.92 mm, P<0.05). There were no accompanying differences in blood pressure, lipid levels, blood glucose, or smoking. Elevation of separate antibody types and circulation immune complex were also associated with increased IMT. In the latter group, systolic blood pressure was higher among seropositive patients compared with those who had no circulating immune complex. Seropositivity was not related to plaque status.

CONCLUSIONS

Seropositivity for C pneumoniae was associated with an increased intima-media thickness in the common carotid artery but not plaque status in hypertensive men at high risk for cardiovascular disease.

Detection of viable Chlamydia pneumoniae in abdominal aortic aneurysms

OBJECTIVES

to investigate the presence of Chlamydia pneumoniae in the wall of abdominal aortic aneurysms (AAAs) and in the aortas of patients without a history of cardiovascular disease.

DESIGN

case-control study.

MATERIALS

twenty-six consecutive patients operated for AAA were compared to 17 controls.

METHODS

aorta was obtained at surgery or autopsy (controls) and prepared for immunohistochemical (IHC) analysis and culture for C. pneumoniae. Throat swabs from 14/26 patients were analysed by PCR for C. pneumoniae. Blood was obtained from 24/26 patients and from 178 70-year-old males.

RESULTS

C. pneumoniae was detected in the aortic aneurysms of 20/26 patients by IHC. C. pneumoniae was cultured from 10 of the 20 IHC-positive patients. Only 1/17 controls was positive for C. pneumoniae by IHC (p=0.0001). PCR was positive for C. pneumoniae in 5/14 patients. Serological analysis by microimmunofluoresence (MIF) showed significantly more high titres of the specific antibodies to C. pneumoniae in patients than in age-matched male controls.

CONCLUSIONS

we conclude that C. pneumoniae is often present in AAAs in a viable form and that C. pneumoniae is linked to the pathogenesis of AAA.

Bordetella pertussis, Bordetella parapertussis, Mycoplasma pneumoniae, Chlamydia pneumoniae and persistent cough in children

Material collected during a prospective pertussis vaccine trial in 1992-95 was examined for Bordetella pertussis (culture and serology), Bordetella parapertussis (culture), Mycoplasma pneumoniae and Chlamydia pneumoniae (PCR). From 64% (99/155) of episodes with cough for less than 100 d, 115 aetiological agents were identified in one southern and one northern subset of DT-recipients. The most common single agent was B. pertussis, representing 56%(64/115), with a median cough period of 51 d, followed by M. pneumoniae 26%(30/115), 23 d, C. pneumoniae 17% (19/115), 26 d, and B. parapertussis 2% (2/115). For co-infections, the median duration of cough was about 60 d. Spasmodic cough for 21 d or more (clinical WHO criteria for pertussis) was present in 82% (41/50) of infections with B. pertussis as single agent, 38% (17/45) with B. parapertussis, 38% (5/13) with C. pneumoniae, 26% (5/19) with M. pneumoniae and 30%(17/56) in cases where no aetiology was found. In children with cough for more than 100 d (n = 78) using all vaccine arms, B. pertussis was responsible in 83% (65/78), in 21%(16/78) together with other agents. Acellular vaccines were more efficient against serious disease than whole cell vaccine. Antibiotic treatment was more common at the southern (34%) study site than at the northern one (12%). The findings indicate that diagnosis should rely on laboratory confirmation, both for rational treatment of an individual case and for monitoring outbreaks.

Chlamydia pneumoniae may be associated with lung cancer. Preliminary report on a seroepidemiological study

Material from 117 consecutive patients with lung cancer was investigated with respect to serological markers for chronic Chlamydia pneumoniae infection. Specific C. pneumoniae IgA antibodies were found significantly more often in patients with lung cancer than in control groups with coronary heart disease and in healthy controls, even after adjustment for smoking. The results suggest that chronic C. pneumoniae infection is common in patients with lung cancer.

Evidence of 2 waves of Chlamydia pneumoniae infection in Gävle, Sweden, 1990-96

Chlamydia pneumoniae is a common respiratory tract pathogen. The majority of adults have serological evidence of previous exposure. Most infections are probably asymptomatic or subclinical. Recent studies have implicated C. pneumoniae as a risk factor for the development of cardiovascular disease. It was therefore of interest to study new blood donors collected between the years of 1990 and 1996 for the purpose of delineating the epidemiological situation in the Gävle area of Sweden. Sera from all first time blood donors over a 7 y period were tested for IgG, IgA and IgM antibodies to C. pneumoniae with a microimmunofluorescence test (MIF). Donors were subjectively healthy individuals between 18 and 65 y of age, (913 M, 752 F). Exposure to C. pneumoniae, expressed in terms of specific IgG antibodies in titres of > 1/32, increased for men in 1990-92 and for women in 1990-93. There was a decrease the following year for both sexes, followed by another increase in 1994-95. IgG antibodies in titres of > or = 512, and IgA antibodies in titres of > or = 1/64, were increased in 1990-91 for men and in 1994-96 for both sexes. The prevalence of specific antibodies increased throughout the 7 y period except for women 1995-96. Men had higher antibody titres than women throughout the entire study period. The results indicate that two waves of largely subclinical infection occurred in our area over the years 1990-96.

Chlamydia pneumoniae infection associated with multi-organ failure and fatal outcome in a previously healthy patient

Chlamydia pneumoniae has been associated with respiratory infections and with cardiovascular disease. We describe here a patient with multi-organ failure and fatal outcome in whom C. pneumoniae was implicated as a causative agent. Serological analysis for C. pneumoniae was done by immunofluorescence. Immunohistochemistry was carried out with avidin-biotin peroxidase staining. The patient had pneumonia I month prior to death. C. pneumoniae was detected in the heart and lungs by immunohistochemistry at autopsy. The patient had an antibody pattern suggestive of current or chronic C. pneumoniae infection. Serological analysis for Legionella sp., Mycoplasma pneumoniae, CMV, EBV, enteroviral agents and markers for autoimmune disease were negative. The findings suggest C. pneumoniae as the aetiological agent in this case of multi-organ failure.

Chlamydia pneumoniae but not cytomegalovirus antibodies are associated with future risk of stroke and cardiovascular disease: a prospective study in middle-aged to elderly men with treated hypertension

BACKGROUND AND PURPOSE

Several cross-sectional and prospective studies have indicated that high titers of antibodies to Chlamydia pneumoniae and cytomegalovirus (CMV) are associated with coronary heart disease. The aim of the present study was to examine whether elevated titers of antibodies to these pathogens are predictive of not only coronary but also cerebrovascular disease.

METHODS

Serum titers of antibodies to C pneumoniae (IgM, IgG, IgA, IgG immune complex) and CMV (IgG) were determined at baseline (n=130) and after 3.5 years (n=111) in a total sample of 152 men. All individuals had treated hypertension and at least 1 additional risk factor for cardiovascular disease (hypercholesterolemia, smoking, or diabetes mellitus) and constituted 93% of a randomly selected subgroup (n=164) of patients participating in a multiple risk factor intervention study.

RESULTS

Elevations of any or both of the IgA or IgG titers to C pneumoniae at entry or after 3.5 years were found in 84 cases (55%). Of those with high titers at entry, 97% remained high at the 3.5 year reexamination. After 6.5 years of follow-up, high titers to C pneumoniae at entry were associated with an increased risk for future stroke (relative risk [RR], 8.58; P=0.043; 95% CI, 1.07 to 68.82) and for any cardiovascular event (RR, 2.69; P=0.042; 95% CI, 1.04 to 6.97). A high serum titer of antibodies to CMV was found in 125 cases (85%), and this was not associated with an increased risk of future cardiovascular events.

CONCLUSIONS

Seropositivity for C pneumoniae, but not for CMV, was associated with an increased risk for future cardiovascular disease and, in particular, stroke.

Association of Chlamydia pneumoniae with otitis media in children

Chlamydia pneumoniae is a common cause of acute and persistent respiratory tract infections. The prevalence of C. pneumoniae was studied using the polymerase chain reaction (PCR) in throat swabs from 85 consecutive children with respiratory tract infections and 86 healthy children. In retrospect, it became evident that this study was conducted in the midst of a local C. pneumoniae epidemic. 38 (45%) of the sick children and 5 (5.7%) of the healthy children were positive for C. pneumoniae by PCR. 26 of the sick children (mean age 6.4 years) were found to have otitis media either at the time of examination or shortly thereafter. Six of 9 children with acute otitis media were PCR positive for C. pneumoniae and 7 of the 9 had specific antibody responses indicating active infection. 10 of 17 children diagnosed as having otitis media with effusion were found to be positive for C. pneumoniae by PCR. Seven children had or developed persistent otitis media with effusion. Chlamydia pneumoniae was demonstrated by PCR from the middle ear fluid in 1 of the children. The results obtained from this study indicate that C. pneumoniae may be involved in the aetiology of otitis media.

The prevalence of chronic Chlamydia pneumoniae infection as detected by polymerase chain reaction in pharyngeal samples from patients with ischaemic heart disease

AIMS

Cross-sectional serological studies have suggested an association between ischaemic heart disease and infections from Chlamydia pneumoniae and Helicobacter pylori. We therefore sought to find out if patients with ischaemic heart disease had an increased prevalence of C. pneumoniae in the pharynx. As the course of the C. pneumoniae infection remains unclear, both acute and follow-up samples were taken and compared with antibody levels.

METHODS AND RESULTS

We studied 282 patients with ischaemic heart disease. One hundred and two subjects without history or symptoms of ischaemic heart disease served as controls. Pharyngeal specimens for polymerase chain reaction detection of C. pneumoniae, and blood samples for C. pneumoniae and H. pylori antibody detection, were collected. In patients with positive polymerase chain reaction or C. pneumoniae IgA titres > or = 32, indicating current infection, convalescent samples were taken at least 6 weeks later. An immunofluorescent antigen detection test was used to confirm the presence of C. pneumoniae elementary bodies in specimens found to be polymerase chain reaction positive. The prevalence of positive polymerase chain reaction tests was 36% among patients and 22% among controls (P<0.05). Forty-seven percent of patients with positive polymerase chain reaction remained positive in the convalescent test. Elevated C. pneumoniae IgG titres > or = 512 were found in 39% of patients and 26% of the controls (P<0.05). IgA titres > or = 32 were found in 46% of the patients and 44% of the controls (ns). Antibody titres remained largely unchanged at convalescent testing. Two patients and none of the controls had IgM titres > 16. There was no link between positive H. pylori serology and positive C. pneumoniae polymerase chain reaction tests.

CONCLUSIONS

The high prevalence and persistence of positive pharyngeal C. pneumoniae polymerase chain reaction and elevated antibody titres in patients with ischaemic heart disease indicate a chronic infection. The pharyngeal presence of C. pneumoniae might contribute to a low grade inflammatory activation or be a source for further spread of the bacteria to atherosclerotic vessels.

Helicobacter pylori serology in elderly people: a 21-year cohort comparison in 70-year-olds and a 20-year longitudinal population study in 70-90-year-olds

AIMS

(i) to compare Helicobacter pylori serology in two 70-year-old cohorts in Gothenburg, Sweden, born 21 years apart, (ii) to study H. pylori serology in a 70-year-old cohort over 20 years.

POPULATION AND METHOD

H. pylori serology at the age of 70 was investigated in 98 men and 132 women born in 1901/02 and in 77 men and 113 women born in 1922. In 21 men and 40 women Helicobacter serology was monitored longitudinally with examinations at 70, 81, and 90 years of age. The analyses were performed on frozen samples by use of an in-house enzyme immunoassay with a sensitivity of 0.99, specificity of 1.00 and positive and negative predictive values of 0.96 and 1.00, respectively. Absorbance values <0.500 were interpreted as negative; values of > or = 0.700 were interpreted as positive, and values in between as inconclusive.

RESULTS

The 70-year-old cohort, born in 1922, showed a significantly lower proportion of subjects with positive H. pylori serology in both men (57.1% vs 80.6%) and women (48.7% vs 75.8%) compared with 70-year-olds born in 1901/02. There were no significant sex differences in either cohort. No longitudinal increase or decrease could be demonstrated in those who were examined at 70, 81 and 90 years of age.

CONCLUSIONS

The difference in H. pylori prevalence between the two cohorts may reflect a rapid change in socio-economic conditions in Sweden during this 20-year period.

Chlamydia pneumoniae in children attending day-care centers in Gävle, Sweden

BACKGROUND

The epidemiology of Chlamydia pneumoniae in healthy children has not been established.

METHODS

This investigation used polymerase chain reaction (PCR) to study the epidemiology of C. pneumoniae in presumed healthy children. Four hundred fifty-three children and 142 personnel at 9 day-care centers were investigated for carriage of C. pneumoniae. Children found to be positive by PCR were also investigated with serology, and their family members were tested with PCR.

RESULTS

One hundred and three (22.7%) children had a positive PCR, as had 33 (23.2%) personnel. Fourteen percent of the children younger than 3 years had a positive PCR test compared with 26% of the older children (P < 0.01). No correlation was found between respiratory symptoms and carriage of C. pneumoniae. Mothers were more often positive in the PCR test as compared with fathers (relative risk, 2.59; 95% confidence interval, 1.16 to 5.78). Antibodies to C. pneumoniae were found in 27 of 97 PCR-positive children; only 2 of whom were younger than 3 years.

CONCLUSION

C. pneumoniae can be commonly found in young children attending day care. Most of the youngest children did not develop specific antibodies. Children may have subclinical infections with C. pneumoniae. The organism seems to be easily communicable among individuals living in close proximity.

Demonstration of Chlamydia pneumoniae in patients with chronic pharyngitis

12 patients with longstanding throat symptoms, who were also positive by PCR (polymerase chain reaction) for Chlamydia pneumoniae were selected for a longitudinal study to determine whether C. pneumoniae is an aetiological agent for chronic pharyngitis. Specimens for culture and PCR detection of C. pneumoniae were taken from the retropharyngeal wall and blood specimens were taken for serology. Biopsies were taken from the mucosal membrane of the retropharyngeal wall for histological and immunohistochemical studies. C. pneumoniae was cultured from 4 cases. 10 patients had specific humoral antibodies to C. pneumoniae and 9 had high and increasing specific antibody titres to C. pneumoniae suggesting ongoing infection. The organism was demonstrated in the tissue from the retropharyngeal mucosal membrane by immunohistochemistry in 9 patients. The findings suggest that C. pneumoniae may be an aetiological agent for chronic pharyngitis.

Increased fibrinogen levels are associated with persistent Chlamydia pneumoniae infection in unstable coronary artery disease

AIM

Increased levels of acute phase proteins, e.g., fibrinogen, are related to a poor outcome in unstable coronary artery disease, but the cause of inflammation is unknown. We therefore investigated the prevalence of persistent Chlamydia pneumoniae infection, and its relationship to inflammation in this condition.

METHODS AND RESULTS

In 256 patients participating in the FRISC trial, evaluating the effects of dalteparin (a low molecular weight heparin) in unstable angina or non-Q wave myocardial infarction, Chlamydia pneumoniae IgA antibody titres and levels of fibrinogen, C-reactive protein and troponin T were determined at inclusion. Increased C. pneumoniae IgA antibody titres were significantly more common in the patients (36%) than in a reference population of similar age (19%); P < 0.001. Raised titres were associated with male gender, increasing age, smoking, and elevated concentrations of fibrinogen, C-reactive protein and troponin T. The association between persistent C. pneumoniae infection and increased fibrinogen levels was independent of other risk factors evaluated in multivariate analysis (P = 0.009).

CONCLUSION

Persistent C. pneumoniae infection is common in unstable coronary artery disease. The independent association between increased C. pneumoniae IgA antibody titres and fibrinogen levels indicates that chronic infection could be of importance for disease activity.

Chlamydia pneumoniae in children with acute respiratory tract infections

Children seeking medical attention for acute respiratory tract infections were investigated for evidence of Chlamydia pneumoniae infection. Blood samples were obtained from 367 children. Nasopharyngeal or throat swabs for PCR analysis (polymerase chain reaction) were taken from 360 children. Serology was found to be useful for diagnosis of infection only in children aged > 5 y. Using PCR, a prevalence of 8 and 10% of C. pneumoniae was found in male and female children aged < 2 y; 17 and 19%, respectively, in the age group 2-4 y and 32 and 21%, respectively, in the age group 5-16 y. We conclude that Chlamydia pneumoniae is a common finding in young children with respiratory tract infections. Younger children were more often found to have a moderate disease, but may have been ill for a long period.

Prevalence of Chlamydia pneumoniae in healthy children and in children with respiratory tract infections

BACKGROUND

Chlamydia pneumoniae causes respiratory tract infections in adults, but little is known about its significance for acute or persistent respiratory tract infections in children.

METHODS

We studied the prevalence of C. pneumoniae by polymerase chain reaction in children younger than the age of 11: 85 consecutive children with respiratory tract infections; and 93 children presumed to be healthy. Throat swabs for PCR analysis were taken from all children, and serology was done for 54 of the 85 sick children and from all but one of the presumed healthy children positive for C. pneumoniae by PCR.

RESULTS

PCR was positive in 38 (45%) of the sick children and in 5 (5.7%) of the healthy children. All but 2 of 19 sick children with serologic findings suggesting recent or ongoing infection with C. pneumoniae were positive by PCR. Most children positive for C. pneumoniae by PCR had upper respiratory tract infections. Four children had recurrent respiratory tract infections and otitis media with effusion treated by tubal insertion.

CONCLUSION

The findings suggest that C. pneumoniae is common among children with respiratory tract infections.

Comparison of nasopharyngeal and throat swabs for the detection of Chlamydia pneumoniae and Mycoplasma pneumoniae by polymerase chain reaction

Nasopharyngeal and throat swabs taken from 66 patients presenting at the Department of Infectious Disease with symptoms of upper and lower respiratory tract infection were analysed by use of the polymerase chain reaction (PCR) for Chlamydia pneumoniae and Mycoplasma pneumoniae. A total of 18 patients (27%) were positive by PCR for C. pneumoniae. All 18 patients were positive from throat swabs, and three were also positive from nasopharyngeal specimens. The difference between the outcome of PCR using throat and nasopharyngeal swabs was statistically significant. A total of 7 patients (10.6%) were positive for M. pneumoniae and of these, 6 were positive from throat swabs and 2 were positive from nasopharyngeal swabs. This difference was not statistically significant, probably due to the low numbers of positive patient specimens.

Chlamydia pneumoniae and myocarditis

Sera from 20 male patients with a diagnosis suggestive of myocarditis, perimyocarditis or pericarditis were found significantly more often to have specific IgA antibodies to Chlamydia pneumoniae than sera from healthy blood donors of the same age and from the same time period. A less pronounced difference in IgG titres was found between patients and blood donors, and IgM antibodies were found only in one patient. A striking variation over time in the prevalence of specific antibodies to C. pneumoniae was seen in consecutive male blood donors over a 5-year observation period. The findings were discussed and it was concluded that C. pneumoniae may be associated with inflammatory heart disease.

In vitro activities of azithromycin and doxycycline against 15 isolates of Chlamydia pneumoniae

Fourteen isolates of Chlamydia pneumoniae, 12 from clinically ill patients and 2 from subjectively healthy individuals from an area within a 400-km proximity of Gävle, Sweden, and strain IOL-207, originally from the eye of an Iranian child, were tested for susceptibilities to the antibiotics doxycycline and azithromycin. MICs and minimum chlamydiacidal concentrations were found to correlate well with values reported earlier by other investigators. In addition to MIC and minimum chlamydiacidal concentration testing, testing for the viability of C. pneumoniae after exposure to antibiotic concentrations as high as 50 mg/liter was carried out by passaging antibiotic-treated, infected cell cultures four times in the absence of antibiotics. It was found that all Chlamydia strains were viable after four passages, regardless of antibiotic concentration in the cell culture.

An increase in sudden unexpected cardiac deaths among young Swedish orienteers during 1979-1992

BACKGROUND

Sixteen cases of sudden unexpected cardiac death, 15 males and one female, are known to have occurred among young Swedish orienteers from 1979 to 1992, of which seven cases occurred between 1989 and 1992. This is considered to be indicative of an increased death rate.

RESULTS

Histopathological evaluation showed myocarditis in a higher than expected proportion of cases. In one such case, which we studied before the sudden unexpected death occurred, the victim had suffered a Chlamydia pneumoniae infection verified by serology, and a nucleotide sequence was found in the heart and lung by means of the polymerase chain reaction (PCR) that hybridized with a probe specific for that organism. Male Swedish orienteers do not, however, seem to have an increased rate of exposure to this agent. No further sudden unexpected deaths among young orienteers have occurred over the past 3.5 years. At the beginning of that period, attempts were made to modify training habits and attitudes.

Persistent Chlamydia pneumoniae infection in a Swedish family

Chlamydia pneumoniae, an etiological agent for respiratory tract infection, was found as a cause of persistent infection in a family group. During the observation period of 2 1/2 years, serology and polymerase chain reaction for C. pneumoniae demonstrated a failure to eradicate the organism, despite several prolonged courses of antibiotics known to be effective against chlamydia species.

Diagnostic efficacy of chlamydial antibodies in cervical secretions from pregnant women and adolescent girls

OBJECTIVE

To assess the prevalence of cervical antibodies to Chlamydia trachomatis in two different populations and to correlate the findings to culture, direct fluorescent antibody test (DFA) and serum antibodies.

SETTING

Antenatal clinics and clinic for teenage counselling in Gävle.

PATIENTS

1078 pregnant women attending for routine follow up in the third trimester of pregnancy and 256 teenage girls.

OUTCOME MEASURES

Cervical IgG and IgA antibodies to Chlamydia trachomatis. Cervical cultures for chlamydia. Serum IgG antibodies. DFA tests were used only in the teenage group.

RESULTS

The prevalence of positive culture was 2.0% in pregnant women and 8.6% in teenage girls. In pregnant women cervical IgG > or = 8 and IgA > or = 8 were found in 7.2% and 5.8% respectively and in teenage girls in 6.6% and 2.0% respectively. The agreement between cervical IgG > or = 8 and humoral IgG > or = 32 was 0.76 in the pregnant group and 0.95 in the teenage group. The sensitivity, specificity and positive predictive value (PPV) for cervix IgG > or = 8 to predict a positive culture was 0.64, 0.94 and 0.18 respectively in pregnant women and 0.41, 0.97, 0.53 respectively in teenage girls. Of 31 teenage girls with either positive culture or positive DFA 12 had cervical IgG > or = 8 while five of 225 with negative chlamydia tests had cervical IgG > or = 8 (sensitivity 0.40 and PPV of 0.71). Cervical IgG > or = 16 was found in eight of 31 with positive chlamydia tests and in one of 225 with negative tests (sensitivity 0.26 and PPV 0.89).

CONCLUSIONS

The finding of cervical IgG > or = 16 predicts current chlamydia (culture or DFA) in nearly 90% in a teenage population. It might indicate current infection in spite of negative culture in some cases. For low titres and in a low prevalence pregnant population cervical IgG are not useful for the diagnosis of chlamydia. As the sensitivity is low cervical antibodies cannot be used for screening purposes.

Chlamydia pneumoniae and chronic pharyngitis

Chlamydia pneumoniae has been implicated as an etiological agent for both upper and lower respiratory tract infections. We describe 4 cases of chronic pharyngitis where Chlamydia pneumoniae appears to be the etiological agent. All the patients were non-smokers, and had symptoms of more than 6 months' duration. Disease symptoms seemed to resolve following appropriate antibiotic treatment.

Prevalence of specific antibodies to Chlamydia pneumoniae in children with acute respiratory infections

We investigated 56 boys and 30 girls between the ages of 1 month and 15 years with acute respiratory infections for antibodies to Chlamydia pneumoniae and Mycoplasma pneumoniae. Antibodies were only occasionally found in children less than 10 years of age (4% of boys (1/23) and 5% of girls (1/19). In the age group 10-12 years, antibodies were detected in 55% of boys (4/9) but not in the 2 girls investigated. In the age group 13-15 years, antibodies were detected in 58% of boys (14/24) and in 33% of girls (3/9). Infection caused by M. pneumoniae was found in 13% of boys in the oldest age group.

Expanded gold standard in the diagnosis of Chlamydia trachomatis in a low prevalence population: diagnostic efficacy of tissue culture, direct immunofluorescence, enzyme immunoassay, PCR and serology

OBJECTIVE

To evaluate the diagnostic efficacy of chlamydia culture, direct immunofluorescence (DFA), direct enzyme immunoassay (EIA), polymerase chain reaction (PCR) and serology by defining positive culture or at least two positive non-culture tests as true positive.

SETTING

Three gynaecological departments located in separate areas of Sweden.

PATIENTS AND DESIGN

All pregnant women requesting abortion during a six month period were included. In cases with unconfirmed non-culture tests, reculture with multiple passage and PCR on the culture transport medium was performed for confirmation. Serum was analysed for chlamydial antibodies type IgG, IgM and IgA using microimmunofluorescence.

RESULTS

18 of 419 (4.3%) patients were positive for chlamydia according to the defined criteria. Twelve of 419 (2.9%) were positive in standard culture (primary inoculation). The sensitivity of standard culture, DFA, EIA and PCR were 66.7%, 77.8%, 64.7% and 71.4% respectively. The specificity 100% (by definition), 99.5%, 100%, 100% respectively. The positive predictive value 100% (by definition), 87.5%, 100%, 100% respectively. Negative predictive value 98.5%, 99.0%, 98.5%, 98.9% respectively. Serum IgG titre of > or = 64 and > or = 1024 gave positive predictive values of 10% and 21% respectively.

CONCLUSIONS

When an expanded gold standard is used, the specificity and positive predictive value of the non-culture tests used are comparable with that of standard culture even in this low prevalence population. Standard culture underestimated the chlamydia prevalence by 33%. The prevalence found represents a decrease from 10 to 2.9% of culture verified chlamydia during four years in comparable populations. Chlamydial antibodies of certain immunological classes are not necessarily present in cases with chlamydia.

Chlamydia pneumoniae (TWAR): a common agent in acute bronchitis

Patients seeking medical attention for respiratory infections were investigated with serology and culture for Chlamydia pneumoniae to investigate the prevalence of C. pneumoniae in a specific geographical area and its association with respiratory disease. Evidence for C. pneumoniae infection was found in approximately 25% of cases. 71% of patients with C. pneumoniae had symptoms from the lower respiratory tract as compared to 29% of the others. We conclude that C. pneumoniae can be a major cause of acute bronchitis.

Chlamydia pneumoniae in Swedish patients

Chlamydia pneumoniae infections have earlier been described as mycoplasma-like illnesses in young people, and also appear to be associated with community-acquired pneumonia in adults. In this retrospective study, 12.2% (23/188) of patients with pneumonia who required hospitalization during the 3 years 1985-87 had serological evidence of recent C. pneumoniae infection. Many of these patients had symptoms similar to ornithosis. The most interesting finding was that half of the patients with a 4-fold IgG antibody titre rise to C. pneumoniae also had an increased alkaline phosphatase concentration.

An unusual manifestation of Chlamydia pneumoniae infection: meningitis, hepatitis, iritis and atypical erythema nodosum

A 37-year-old man was admitted to hospital with fever, muscle tenderness, headache and mild exanthema on the right thigh. During his hospital stay, the headache worsened and aseptic meningitis was diagnosed. A bilateral iritis developed, and the exanthema developed into an atypical erythema nodosum. In liver function tests, pathological results were recorded. Vasculitis was suspected but could not be confirmed. All serological tests proved negative except for a fourfold titre rise to Chlamydia pneumoniae. We concluded that the meningitis, hepatitis, iritis and atypical erythema nodosum were most probably due to a C. pneumoniae infection.

Evaluation of a direct fluorescence assay as a screening method in asymptomatic young women

The purpose of the study was to evaluate one rapid antigen test (DFA), in comparison to culture, for the detection of Chlamydia trachomatis in young, asymptomatic women. C. trachomatis was isolated from specimens of 8.6% of the patients studied, and 11.3% had 10 or more elementary bodies (EBs) in their specimens. A lowered cut-off point of the DFA did not affect the sensitivity of the method, but the predictive value of a positive test decreased markedly when the cut-off point was lowered. Patients with symptoms of genital infection, signs of genital infection, or both had a higher DFA sensitivity than those who were asymptomatic. Patients whose specimens yielded 1-9 EBs were reexamined three times, once every fourth week. We found little evidence that those patients should be regarded as falsely negative in culture, since most of them remained negative. In order to minimize the social consequences of a false positive test, the DFA method should not be substituted for culture as a diagnostic tool, especially for screening of asymptomatic groups with a low prevalence of C. trachomatis.

Prevalence of Mycoplasma pneumoniae in subjectively healthy individuals

Subjectively healthy persons were investigated for the presence of Mycoplasma pneumoniae in throat cultures. During a peak period of M. pneumoniae incidence, 13.5% of 758 healthy volunteers were found to harbour the bacterium in the throat. The investigation was continued, and during a subsequent period of 11 months, the incidence of M. pneumoniae isolated decreased to 4.6% of 499 volunteers. All new blood donor sera 1990-1991 (422 sera) were screened for the presence of antibodies to M. pneumoniae; it was found that there was a fluctuating but significant number of individuals with positive serology based on a single test occasion.

Endemic prevalence of Chlamydia pneumoniae in subjectively healthy persons

Subjectively healthy persons were investigated for the presence of Chlamydia pneumoniae (TWAR) with throat cultures using the HL (human lung) cell line. C. pneumoniae was isolated from 11/234 investigated persons.

Chlamydia trachomatis among sexually active teenage girls: influence of sampling location and clinical signs on the detection rate

A total of 707 cultures for Chlamydia trachomatis were obtained from healthy teenage girls attending an adolescence clinic for family planning. Apart from sampling from the endocervix, specimens were also obtained from outside the squamocolumnar junction and from the posterior fornix and cultured separately in order to study whether it was possible to improve the detection rate of C trachomatis by sampling from outside the endocervix. In 91 (12.8%) of the girls a positive culture was found. Of the chlamydia positive samples, 83.5% were obtained from the endocervix and 95% from outside the squamocolumnar junction of the portio. Of the 91 positive cultures, 15 (16.5%) were positive only in the sample obtained from the portio surface. The results indicate that the detection rate of C trachomatis could be improved by extended specimen collection. C trachomatis was isolated significantly more often when there was an ectopy, irrespective of whether the specimens had been collected from the endocervix or from outside the squamocolumnar junction. C trachomatis was particularly common if there was an ectopy and a bleeding at specimen collection. If there was no bleeding at sampling, C trachomatis was equally common in women with as in those without an ectopy.

Does omeprazole improve antimicrobial therapy directed towards gastric Campylobacter pylori in patients with antral gastritis? A pilot study

This double-blind pilot study has been undertaken in order to investigate the effect of amoxicillin and pronounced suppression of gastric acid secretion on mucosal colonisation with Campylobacter pylori (CP). Twenty four CP-positive patients were included in the study and assigned to 14 days of treatment in either one of the following three therapy groups: Group 1: Omeprazole 40 mg o.m. + Amoxicillin 750 mg b.i.d (9 pat); Group 2: Omeprazole 40 mg o.m. (8 pat); Group 3: Amoxicillin 750 mg b.i.d (7 pat). Gastroscopy with biopsy for culture and histology was performed pre-entry, at cessation of therapy and four weeks later. In the group receiving omeprazole and amoxicillin in combination 5 out of 8 patients were negative for CP four weeks after stopping treatment, while in the amoxicillin and the omeprazole groups respectively one (1/7) and none (0/8) were negative. Except for one patient who was withdrawn because of severe diarrhoea, only minor adverse effects occurred.