Infection with Mycoplasma pneumoniae in civilians in the Netherlands

Mycoplasma Pneumoniae: A Cross-sectional Population-based Comparison of Disease Severity in Preschool and School-age Children

BACKGROUND

Mycoplasma pneumoniae causes epidemics of upper respiratory disease and pneumonia. It is thought that M. pneumoniae usually causes milder upper respiratory disease in preschool children, with a greater chance of pneumonia in school-age children. In this population-based cross-sectional study, we present evidence that severe M. pneumoniae infection is more common in preschool children than previously thought.

METHODS

During an M. pneumoniae epidemic in our area, widespread health service and public awareness lead to extensive testing for M. pneumoniae. Medical records of hospital-referred M. pneumoniae-positive children were assessed retrospectively for respiratory disease and chest radiographic results. Severe disease was defined as supplementary oxygen or fluid requirement, mechanical ventilatory support or neurologic disease. Age-specific population figures were used to calculate incidence during the study period. Those who were 0-5-year-olds were considered preschool, whereas 6-17-year-olds were considered school-aged.

RESULTS

Thirty-seven preschool and 55 school-age children were referred to the hospital and tested positive for M. pneumoniae. Twenty-two (60%) preschool and 23 (42%) school-age children had severe disease [incidence 56 vs. 29 per 100,000; relative risk: 1.9; 95% confidence interval (CI): 1.06-3.4; P = 0.03]. Twenty (54%) preschool and 19 (35%) school-age children had severe pneumonia (incidence 51 vs. 24 per 100,000; relative risk: 2.1; 95% CI: 1.1-3.9; P = 0.03).

CONCLUSIONS

During an M. pneumoniae epidemic in Akershus and North Oslo in 2011-2012, preschool children infected with M. pneumoniae had significantly higher risk of severe disease, particularly severe pneumonia, when compared with school-age children. M. pneumoniae should be considered a potential pathogen in younger children with respiratory distress, particularly during an epidemic period.

Mycoplasma pneumonia Infection: A Possible Trigger for Immune Thrombocytopenia

Mycoplasma pneumonia (M. pneumonia) is usually not considered among the several pathogens that induce immune thrombocytopenia (ITP). We report a child with a clinical diagnosis of severe ITP that was associated with M. pneumonia pneumonia, and review the few cases described in the English literature. We suggest that thrombocytopenia associated with M. pneumonia infection may constitute a subset of ITP, although unlike ITP it occurs concomitantly with the infection and tends to be more severe than "classic" ITP. We recommend that prompt specific antibiotic and immune modulating treatment should be initiated in appropriate clinical settings.

An unrecognized epidemic of Mycoplasma pneumoniae infection in Vienna

Mycoplasma pneumoniae infection shows epidemiological peaks with a 2- to 10-fold increased incidence every four to seven years. The regional epidemiology of M. pneumoniae infection is important with regard to empirical antibiotic treatment of community-acquired respiratory tract infections, which are the most common cause for visiting a physician. To date, no data on the epidemiology of M. pneumoniae in central Europe have been published. In the present study, the results of M. pneumoniae serology performed at the Clinical Division of Virology at Vienna General Hospital (a 2,140-bed university teaching hospital with an average of 94,000 admissions/year and 430,000 outpatient visits/year) in the 10-year period from January 1995 to December 2004 were analyzed retrospectively. Antibody titers > or = 1:64 in complement fixation tests were considered indicative of acute or recent mycoplasma infection. The annual total number of serum specimens tested for anti-M. pneumoniae antibodies remained stable throughout the study period (median: 2859 samples/year, range: 2257-3338). The annual median number of patients with high M. pneumoniae titers was 13. A major epidemiological peak (43 patients) was observed in 2000, the epidemic starting in late 1999 and ending in 2001. A surveillance or reporting system for M. pneumoniae infections (i.e. positive serological results for M. pneumoniae) would be useful for physicians caring for patients with community-acquired respiratory tract infections.

Epidemiology and etiology of community-acquired pneumonia

The seriousness of community-acquired pneumonia (CAP), despite being a reasonably common and potentially lethal disease, often is under estimated by physicians and patients alike. CAP results in more than 10 million visits to physicians, 64 million days of restricted activity, and 600,000 hospitalizations. This article discusses the epidemiology and bacterial causes of CAP in immunocompetent adults and the severe acute respiratory syndrome coronavirus.

Community-acquired pneumonia in ambulatory patients: relative importance of atypical pathogens

The presence of atypical pathogens in community-acquired pneumonia is difficult to diagnose; culture is time-consuming and requires considerable expertise and serological identification may be inaccurate. Nevertheless, the increasing importance of atypical organisms has been recognised in recent years. Variations in aetiology have been detected in different geographical regions and different patient populations. The season of the year may also influence aetiology, and some infections follow a cyclical pattern. When an atypical pathogen is suspected, a macrolide antibiotic is an appropriate choice as, in addition to activity against these organisms, they are usually effective against the Gram-positive and Gram-negative respiratory pathogens implicated in community-acquired pneumonia.

Chlamydia pneumoniae and Mycoplasma pneumoniae in children with acute respiratory infection in general practices in The Netherlands

In this retrospective study Chlamydia pneumoniae and Mycoplasma pneumoniae infections were detected by polymerase chain reaction (PCR) in samples (n = 457) from children presenting with acute respiratory infection to general practitioners during 1992-97. Samples were collected in autumn and winter, and from 1994 onwards in spring and summer also. Overall, C. pneumoniae and M. pneumoniae were detected in throat or nasal samples by PCR in 3.1% and 2.4% of the cases, respectively. The proportion of both C. pneumoniae and M. pneumoniae infections varied between 0% and 6.9% over the years studied, whereas seasonal proportions varied from 1.8 to 9.1% and 1.2 to 4.5%, respectively. For both microorganisms the lowest proportion was detected during winter and the highest in summer. C. pneumoniae could already be detected by PCR in patients under 4 y of age, an observation not made in sero-epidemiological studies. In conclusion, both C. pneumoniae and M. pneumoniae infections play a minor role in children presenting with acute respiratory infection.

A latex agglutination test for the detection of Mycoplasma pneumoniae in respiratory exudates: a comparative study with a commercially available DNA-probe test

We prepared polyclonal antibody specific to Mycoplasma pneumoniae. Using this antibody, we developed a latex agglutination test (LAT) for detecting the organism in respiratory exudates as rapid diagnosis of M. pneumoniae infection. Further, LAT was compared with DNA-probe test (DP) which was the only commercially available test for the rapid detection of the organism. In LAT, both M. pneumoniae and M. genitalium give positive agglutination, but the titer of M. genitalium was significantly lower than that of M. pneumoniae. The detection limit of LAT was 2 x 10(5) CFU/ml and that of DP was 5 x 10(4) CFU/ml in vitro. It was considered that target molecules in LAT were accumulated in the pharyngeal portion of the patients, because of their long half-life at 37 C. However, ribosomal RNA which was target molecule in DP was destroyed at 37 C much sooner, and the accumulation could not be expected. Actually, positive rate in LAT was higher than that in DP among clinical specimens in which M. pneumoniae was detected by culture method. The procedure of LAT is much easier and more rapid than that of DP in which radioactive isotope is required. LAT could be the choice of test for rapid diagnosis of M. pneumoniae infection.

A sensitive method for detecting the fermentation-inhibition antibody to Mycoplasma pneumoniae

The fermentation-inhibition (FI) test for Mycoplasma pneumoniae was improved by using a combination of guinea pig complement and gamma globulin-depleted horse serum in place of unheated whole horse serum employed in the conventional assay system. As the test antigen for the new FI assay system, M. pneumoniae filtrated through a 3.0 microns membrane filter was used. Owing to the strong augmenting effect of guinea pig complement, the FI activity of rabbit immune serum was increased 32-fold in the new system compared with the conventional system. Furthermore, IgM antibody, which is barely detectable by the conventional system, could easily be titrated by the new system. With this sensitive method, rapid rise of FI titer was clearly demonstrable in most children with acute M. pneumoniae infections, and a prevalence of FI or growth-inhibitory antibody among healthy adults in Japan (82%) was revealed.

Application of an indirect immunofluorescence test for detection of Mycoplasma pneumoniae in respiratory exudates

We prepared polyclonal antibody specific to Mycoplasma pneumoniae and examined the conditions influencing the ability of an indirect immunofluorescence test to detect the specific antigen in respiratory exudates. The antibody did not cross-react with normal human serum or with respiratory exudates from 10 healthy persons. Cross-reactivity of the antibody with species of mycoplasmas other than M. genitalium was fully diminished when absorbed with horse serum and yeast extract, components of the culture medium. Though the absorbed antibody cross-reacted with M. genitalium, the titer was significantly lower than when tested against M. pneumoniae. Two types of antigen-specific fluorescence were observed in clinical specimens: one is large or small fluorescent granular aggregates found in mucus, and the other is fine fluorescent particles diffused on the entire surface of small epithelial cells. Throat smears from 49 patients with serologically confirmed M. pneumoniae infections were examined by our indirect immunofluorescence method. Positive results were obtained in 42 cases, many of which were positive before a rise in serum antibody titer could be demonstrated, indicating that the method is useful for a preliminary diagnosis at an early stage of the infection.

Survival of Mycoplasma hyorhinis in trypsin solutions

The survival of four strains of Mycoplasma hyorhinis in stock solutions of trypsin was tested at 22, 4 and -15 degrees C. Low (10(4)-10(5) cfu/ml) and high (10(6)-10(7) cfu/ml) initial concentrations of each strain were used, each was tested three times. A regular decrease of low and high concentrations (1 log in 10 and 20 min, respectively) was seen at 22 degrees C. At 4 degrees C the low concentrations showed a reduction of about 1 log/h, while apart from one strain high concentrations hardly decreased during the first 6 h and the survival time ranged from 24 to more than 30 h at the end of which there was a reduction of 4 logs. At -15 degrees C low concentrations survived up to 1 week in only one of the three tests, high concentrations survived for more than 12 weeks (reduction 3 logs). These latter results suggest that mycoplasmas may be present in trypsin as clumps, which deteriorate very slowly. A study was also performed to compare the sensitivity of different cultural procedures for detecting mycoplasmas.

Laboratory diagnosis of Mycoplasma pneumoniae infection. 1. Direct detection of antigen in respiratory exudates by enzyme immunoassay

Direct and indirect antigen capture enzyme immunoassays (Ag-EIA) have been developed for the detection of Mycoplasma pneumoniae in nasopharyngeal aspirates or sputum from respiratory infection. The sensitivity of the two Ag-EIA were similar, but the indirect method using polyclonal rabbit and guinea-pig antisera was more convenient. The Ag-EIA had a detection limit of 10(4-4.5) colony-forming units/ml of sample. It was specific for M. pneumoniae and gave a low level response with M. genitalium. There were no cross-reactions with 10 other species of mycoplasmas. Tests with a wide range of bacteria and chlamydia group antigen, representing agents sometimes found in the respiratory tract, were also negative. At the current level of development, the Ag-EIA detected about 90% of specimens that were also positive for culture; 43% of specimens from culture-negative--seropositive patients gave a positive result. The overall pattern of results indicated that while antigen detection is a quick and effective substitute for the slow culture method, serological examination for specific IgM antibody is also necessary to give a complete diagnostic coverage.

Clinical efficacy of ciprofloxacin versus doxycycline in the treatment of non-gonococcal urethritis in males

In a randomised study the clinical efficacy of ciprofloxacin was compared with that of doxycycline administered in two different dosage schemes to male patients suffering from non-gonococcal urethritis. Fourteen days after completion of therapy (day 21) pyuria was absent in 30 of 100 patients in the ciprofloxacin group; Chlamydia trachomatis was isolated from five and Ureaplasma urealyticum from eight patients. In the 100 mg doxycycline group (n = 60) pyuria was absent in 36 patients (60%) and Ureaplasma urealyticum was isolated from six patients on day 21. In the 200 mg doxycycline group (n = 45) pyuria was absent in 18 patients (40%) and Ureaplasma urealyticum was isolated from two patients on day 21. Side-effects were mild and transient in all groups. It is concluded that ciprofloxacin given in a dosage of 1 g for seven days is not effective in the treatment of non-gonococcal urethritis.

Changes in the epidemiological pattern of Mycoplasma pneumoniae infections in Denmark. A 30 years survey

A seroepidemiological survey has shown a remarkable shift in the previously reported regular cyclic pattern of Mycoplasma pneumoniae epidemics which culminated every 4.5 years during the period 1958-74. The last of four regular epidemics occurred in 1972. It was followed by 'premature' epidemics in 1975 and 1977/8 which inaugurated a change from an epidemic to an endemic pattern of the infection in Denmark. Over the following 9 years (1978-86) there has been an irregular but significant decrease in the annual number of seropositive samples with the usual high incidence during winter seasons. This endemic period terminated in the fourth trimester of 1987 with the development of a new epidemic. The hypothesis is advanced that a sixfold increase of children in day care may have influenced the change from an epidemic to an endemic situation which after 9 years led to a new epidemic of M. pneumoniae infection.

Detection of specific IgM antibodies for the diagnosis of Mycoplasma pneumoniae infections: a clinical evaluation

The diagnostic value of detection of specific IgM antibodies was analysed in Mycoplasma pneumoniae infections. In a retrospective clinical and serological study, M. pneumoniae IgM antibodies were determined by a mu-capture ELISA using enzyme-labelled antigen. The study group consisted of 91 patients with significantly raised titers in paired sera or a single high titer of complement fixation antibodies. About 40% of the patients had been treated with antibiotics ineffective against M. pneumoniae infections prior to admission to hospital. Treatment with erythromycin or tetracycline was shown to give a shorter period of fever compared to if no or ineffective therapy was given. Specific IgM antibodies were detected in about 80% of sera sampled 9 days or more after onset of symptoms. In sera sampled at 7-8 days after onset IgM antibodies were found in about 40% of the sera but only occasionally in sera sampled earlier. In the age group 0-20 years 88% of the patients developed an IgM response. In the higher ages (greater than 60 years) a significantly lower rate of IgM responders was observed.

Sexually communicable micro-organisms in human semen samples to be used for artificial insemination by donor

Two hundred and thirty seven semen samples from 10 institutes for artificial insemination by donor (AID) in Belgium and the Netherlands were tested for the presence of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum, herpes simplex virus, and cytomegalovirus. The incidence of these micro-organisms in the semen samples was 0%, 6.3%, 4.6%, 35.9%, 0%, and 0.4% respectively, and 47% of all samples were infected with one or more of the micro-organisms. As the ejaculates from which the samples had been taken had already been, or would be, used for AID, the exclusion of microbiological contamination with sexually communicable micro-organisms before insemination is indicated.

Hemophagocytosis secondary to Mycoplasma pneumoniae infection

A patient with hemophagocytosis secondary to Mycoplasma pneumoniae is described. This adds another entity to the already protean manifestations of M. pneumoniae infection.

Comparison of two methods for detection of mollicutes (Mycoplasmatales and Acholeplasmatales) in cell cultures in the Netherlands

A total of 1949 cell cultures was tested for contamination with mollicutes by cultivation on and in mycoplasma media, 25.7% of the cell cultures was positive, 243 strains of Mycoplasma hyorhinis were isolated. Furthermore, mainly M. arginini and M. orale were detected, less often Acholeplasma laidlawii, M. fermentans and M. pneumoniae. Optimal conditions for isolation were discussed. About one third of 217 hybridoma cultures and two third of 57 myeloma cultures proved to be contaminated, all with M. hyorhinis. A DNA fluorochrome staining method (DAPI-test) was compared to cultivation for testing 1039 cell cultures. The efficiency of the DAPI-test could be estimated to be about 96% that of cultivation about 89%, but cultivation is more specific. The highest assurance is obtained when both methods are applied.

Evaluation of roxithromycin in the treatment of non-gonococcal urethritis in males

One-hundred and fifty-two male patients suffering from non-gonococcal urethritis were treated with an oral dosage of 300 mg roxithromycin daily for seven days. Chlamydia trachomatis was isolated from the urethra in 53 patients (35%), and Ureaplasma urealyticum in 42 patients (28%). After treatment, 49 (92%) of the 53 patients with positive Chlamydia trachomatis cultures and 34 (81%) of the 42 patients with positive Ureaplasma urealyticum cultures had negative cultures at follow-up. A clinical cure was observed in 137 patients (90%). Ten patients (7%) showed side effects consisting of nausea, sensation of distended abdomen, headache and fatigue. Seventy-eight male patients suffering from nongonococcal urethritis were treated with an oral dosage of 2 X 150mg roxithromycin daily for seven days. Chlamydia trachomatis was isolated from the urethra in 22 patients (28%), and Ureaplasma urealyticum in 30 patients (38%). After treatment, all of the 22 patients with formerly positive Chlamydia trachomatis cultures and 23 (77%) of the 30 patients with formerly positive Ureaplasma urealyticum cultures were negative at follow-up. A clinical cure was observed in 70 patients (90%). Three patients (4%) showed side-effects consisting of nausea and headache. It is concluded that roxithromycin is a good alternative to tetracycline and erythromycin in the treatment of non-gonococcal urethritis in males.

In vitro activity of the two new 4-quinolones A56619 and A56620 against Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum and Gardnerella vaginalis

The in vitro activity of tetracycline, ciprofloxacin and two recently developed 1-aryl-fluoroquinolones, A56610 and A56620, was tested against 65 beta-lactamase-negative and 35 beta-lactamase-positive Neisseria gonorrhoeae strains, 12 Chlamydia trachomatis, 50 Mycoplasma hominis, 28 Ureaplasma urealyticum and 50 Gardnerella vaginalis strains. In the case of Chlamydia trachomatis and Mycoplasma hominis both the MIC and the MBC were determined. The MIC90 of ciprofloxacin for Neisseria gonorrhoeae was 0.008 microgram/ml and of A56619 and A56620 less than or equal to 0.03 microgram/ml. No difference was observed between the activity against beta-lactamase-negative and beta-lactamase-positive strains. The MIC90 values of of ciprofloxacin and A56620 for Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum were identical, the values being 2 micrograms/ml, 1 micrograms/ml and 4 micrograms/ml respectively. The MIC90 of A56619 for Chlamydia trachomatis and Ureaplasma urealyticum was 0.5 micrograms/ml and 1 microgram/ml respectively. The MBC90 values of the three quinolones for Chlamydia trachomatis and Mycoplasma hominis were less than or equal to 2 micrograms/ml. The activity of the quinolones against Gardnerella vaginalis was rather low, the MIC90 being greater than or equal to 4 micrograms/ml. It is concluded that A56619 and A56620 might be useful for single-dose therapy of gonococcal infections.

Secondary bacterial infections in children with proved Mycoplasma pneumoniae

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Inhibition of growth of Mycoplasma dispar by DL-alpha-difluoromethyllsine, a selective irreversible inhibitor of lysine decarboxylase, and reversal by cadaverine (1,5-diaminopentane)

DL-alpha-Difluoromethyllysine was shown to be a potent inhibitor of lysine decarboxylase from Mycoplasma dispar. The inhibition appeared to be specific since neither difluoromethylornithine nor difluoromethylarginine, known to inhibit other decarboxylases, inhibited the reaction catalyzed by lysine decarboxylase in extracts of M. dispar. Inhibition was irreversible since extensive dialysis could not overcome the inhibitory effect exerted by difluoromethyllysine. Difluoromethyllysine (1 mM) also totally blocked the growth of M. dispar when added at the beginning of the growth period, while 1 mM cadaverine, the product of the reaction, reversed this inhibitory effect when added to the culture medium. When difluoromethyllysine was added during the logarithmic growth phase of Mycoplasma, it inhibited the increase of the growth; 1 mM cadaverine again partially reversed this inhibitory action.

Use of the enzyme-linked immunosorbent assay for the early diagnosis of Mycoplasma pneumoniae infection

IgM and IgG antibodies to Mycoplasma pneumoniae were measured in 147 sera from four groups of patients by means of an indirect enzyme-linked immunosorbent assay (ELISA) and the results compared with those obtained by other methods. A good correlation was demonstrated between the complement fixation test and ELISA-IgM and to a lesser extent ELISA-IgG; for the metabolic inhibition test the reverse was the case. The indirect haemagglutination test appeared to detect mainly IgM antibodies. Low levels of IgM antibodies were detected by ELISA in 60 sera of children not suffering from pneumonia. However, if only high titres (greater than 800) were regarded as indicative of Mycoplasma pneumoniae infection, a presumptive diagnosis could have been made in 42 of 73 single acute phase sera from patients. Comparable results were obtained with IHA. The diagnostic level of IgM antibodies. was reached during the second week of the disease. It is concluded that examination of a single serum sample by either ELISA-IgM or IHA may assist in early diagnosis of Mycoplasma pneumoniae infection.

Age-related prevalence of complement-fixing antibody to Mycoplasma pneumoniae during an 8-year period

We determined the age-related prevalence of complement-fixing antibody to Mycoplasma pneumoniae from the computerized laboratory results of our routine diagnostic department. The material consisted of about 58,000 sera from an 8-year period, 1971 to 1978. Among children less than 1 month old, the frequency of complement-fixing antibody of titers greater than or equal to 8 was low (23%), and no decrease representing loss of maternal antibody was seen thereafter. An unexpectedly early increase in the antibody prevalence up to 62% was seen by 6 months of age. The frequency of antibody was high among young children from the age of 4 months, in whom symptomatic infection due to M. pneumoniae is rare. The frequency of higher titers (greater than or equal to 32) and the geometric mean titer increased more slowly, coinciding with the known age distribution of symptomatic M. pneumoniae disease; the frequency of high titers and the geometric mean titer peaked at the age of 7 to 10 years. Two explanations for the high frequency of complement-fixing antibody to M. pneumoniae in young children are discussed. It may be due to an asymptomatic infection caused by M. pneumoniae or to a nonspecific stimulus by lipids of other organisms, plants, or tissues leading to production of antibodies crossreacting with M. pneumoniae, or it may be due to both of the above. During the study, two extensive epidemics due to M. pneumoniae occurred in Finland, but the prevalence of complement-fixing antibody bore no correlation with these peaks of occurrence.

Comparison of various atmospheric conditions for isolation and subcultivation of Mycoplasma hyorhinis from cell cultures

The efficiency of aerobic incubation was compared with incubation under various oxygen and carbon dioxide conditions for the isolation and subcultivation of three strains of Mycoplasma hyorhinis from VERO-cell cultures and subcultivation of three laboratory strains. Under anaerobic conditions with a low oxidation-reduction potential (at or below -115 mV) as obtained in jars, with catalysts, containing mixtures of 5%-10% CO2 in H2, very poor or no growth of any of the six M. hyorhinis strains was observed. When traces of oxygen were present (that is, under conditions with higher oxidation-reduction potentials, e.g. when omitting the catalyst in the above gas mixtures or in 5% CO2 + 95% N2) isolation from cell cultures was successful in most tests, but subcultivation of these primary isolates was seldom possible under these semi-anaerobic conditions. However, in most cases these primary isolates could be subcultivated aerobically, although aerobic conditions were unsatisfactory for isolation in about half of the experiments. Isolation of M. hyorhinis was optimal in 5% O2 + 95% N2, under which condition the isolates could also always be subcultivated. Isolation failed occasionally when 5% O2 + 5% CO2 + 90% N2 was used, thus indicating that 5% CO2 was slightly inhibitory. 5% CO2 in air and 10% CO2 either in air, H2 or N2 were also inadequate for isolation from cell cultures. In contrast to the findings with these cell culture-adapted M. hyorhinis strains, the laboratory strains could be subcultivated easily under all conditions tested except those with an oxidation-reduction potential at or below -115 mV; 100% CO2 was inhibitory for all 6 strains. Our findings may partly explain why M. hyorhinis is often considered "non-cultivable" on artificial media once adapted to cell cultures. The findings emphasize the need to employ also a micro-aerophilic condition (5% O2 in 95% N2) in the examination of cell cultures for mycoplasma.

Occurrence of serologically verified Mycoplasma pneumoniae infections in Finland and in Scandinavia in 1970--1977

This study analyses the numbers of serologically verified Mycoplasma pneumoniae infections in Finland as a whole and by regions, and in Scandinavia in 1970--77 on the basis of reports collected in the countries concerned. Two peaks of occurrence were found to have extended over most parts of Finland and across Scandinavia; in addition, there were separate local epidemics. Thus, M. pneumoniae infections showed a periodicity of occurrence, but not a regular cyclic pattern. The figures do not necessarily reflect the true incidence of M. pneumoniae infections in the areas investigated.

Mycoplasma pneumoniae infection. A retrospective review of 103 hospitalised children

The clinical aspects of Mycoplasma pneumoniae infection in 103 children under 12 years admitted to hospital over an eight-year period were reviewed retrospectively. Respiratory illnesses occurred in 87 (85%) cases. The prevalence of lower respiratory tract involvement was similar in both pre-school and school children. Cough was the commonest symptom at all ages. Coryzal symptoms and wheeze were common in pre-school children. Most infants had signs of pharyngitis or otitis media. Non-specific symptoms--fever, lethargy, malaise, anorexia and vomiting--were common accompaniments in children older than one year of age. Non-respiratory illnesses in 16 (15%) patients included gastroenteritis, convulsions, non-specific skin rashes and limb pains. The duration of stay in hospital ranged from two to 30 days (median five days) with apparent clinical recovery and resolution of chest X-ray abnormalities within three months in 78 (76%) patients seen for review.

Isolation of mycoplasma species from infertile patients: an epidemiological contribution

In this study the presence of Mycoplasma species in patients suffering from infertility was examined. 41 women and 37 men were examined, including 31 couples, and ten single women and six single men. Samples of vaginal and cervical mucus were taken from each woman, and samples of seminal fluid from each man. Identification and typing of the organisms were performed on the basis of microscopic and cultural characteristics and inhibition of growth by specific antibodies. Out of the 78 patients examined, 35 harboured Mycoplasma, either as Ureaplasma urealyticum or Mycoplasma hominis. Further investigation is needed to determine the clinical significance of these findings.

The incidence and aetiology of respiratory tract infections in general practice--with emphasis on Mycoplasma pneumoniae

The incidence of respiratory tract infections in patients seeking medical advice at a community care centre (Dalby) during 1973 and 1974 was studied. About every third patient seen at this primary health station presented with signs of such infections. In the age groups less than 10, 10-19, 20-39, 40-59 and greater than or equal to 60 years, respiratory tract infections accounted for 65, 45, 32, 18 and 9% of the fotal number of diagnoses made during 1974. The aetiology of acute respiratory tract infections in a series of patients seen at this health station was studied. The series included randomly selected cases, but excluded children under seven years of age and patients presenting with signs of acute otitis media and tonsillitis. Attempts to establish the aetiology were made on the basis of the history, the clinical examination, and cultures for beta-haemolytic streptococci and Mycoplasma pneumoniae, complement foxation tests for influenza A and B, para-influenza 1, 2, and 3, adeno, cytomegalovirus and respiratory syncytial virus, and Chlamydia psittaci. Paul-Bunnell test and tests for cold agglutinins were also performed. With this test battery, an aetiological diagnosis was obtained in only 33% of the 101 patients studied. The findings suggest an infection with M.pneumoniae in 16%, with beta-haemolytic streptococci in 9%, and with viruses (adeno and para-influenza) in 7% of the patients. The present communication highlights the role of M.pneumoniae in upper respiratory infections, as few data have appeared on such infections in patients seen in general practice. The difficulty of establishing the aetiology of respiratory tract infections and the consequent treatment dilemma is discussed.

Evaluation of a microscopy method for rapid detection and identification of Mycoplasma pneumoniae

A microscopy test that used the typical shape of Mycoplasma pneumoniae cells growing on glass was investigated for its value for diagnostic purposes. Suspensions from 108 throat swabs were infected artificially with 102, 103, and 104 colony-forming units of three M. pneumoniae strains per ml. Agar medium, a diphasic medium, and the microscopy method with liquid medium in cover slip chambers were compared for isolation of the mycoplasmas. The mycoplasms were detected first by the microscopy method in nearly all concentrations tested. Typical M. pneumoniae cells could often be detected after 48 h. No differences were found between a laboratory strain and two low-passage strains. The experimental results suggest that under special circumstances the microscopy method could be a useful tool for isolation and identification of M. pneumoniae.

The protean manifestations of Mycoplasma pneumoniae infection in adults

Mycoplasma pneumoniae is a well recognized respiratory pathogen in children and young adults. In addition, M. pneumoniae infections may also involve other organ systems. Reviewed here are the various clinical syndromes in adults caused by this infectious agent, with emphasis on those which have recently been seen at The New York Hospital. Two previously unreported manifestations of M. pneumoniae infection, cranial nerve mononeuropathy and hepatitis, are described, and the laboratory methods for diagnosis are discussed.

A search for mycoplasma infections in patients with chronic bronchitis

Throat and bronchoscopy specimens for mycoplasma isolation studies were collected from 22 patients with chronic bronchitis and 20 patients without chronic bronchitis. Twenty-six of 50 patients attending a chronic bronchitis clinic had throat, nasal, or sputum specimens collected for attempted mycoplasma isolation, and all of these patients had multiple serum samples taken for mycoplasma antibody studies. Mycoplasmas were recovered from throat and bronchoscopy specimens of the chronic bronchitic and non-bronchitic patients with about equal frequency. The concentration of organisms in the bronchoscopy specimens of two patients with chronic bronchitis was greater than in their throat specimens, suggesting downward spread and multiplication of mycoplasmas rather than contamination by passage of the bronchoscope. Eighty-three per cent of the rises in mycoplasma antibody titre in chronic bronchitic patients occurred during or immediately after an acute respiratory illness, and this relationship of rise in antibody titre to acute illness was significantly more frequent than rises in antibody titre not associated with illness. We suggest that mycoplasmas may be present in the bronchi of some patients suffering from chronic bronchitis and that, while such mycoplasma infections are often silent, they may become sufficiently active during infection by other agents to stimulate a mycoplasma antibody response.