The protean manifestations of Mycoplasma pneumoniae infection in adults

Mycoplasma capping on lymphocytes

When mycoplasmas infect lymphocytes they behave as multivalent ligands and cap on the lymphoid cell surface in the absence of added specific antibody. There is an apparent high correlation between mycoplasma capping and blast transormation of the infected lymphocytes. Mycoplasma caps are shed from the surface of cells as an aggregate containing host membrane vesicles. This novel interaction may suggest a physiological role for the phenomenon of capping and may play a part in mycoplasma pathogenesis.

Isolation of Mycoplasma pneumoniae from the synovial fluid of a hypogrammaglobulinaemic patient in a survey of patients with inflammatory polyarthritis

Mycoplasmas were not isolated from synovial fluid or membrane specimens taken from 41 patients suffering from inflammatory polyarthritis. However, Mycoplasma pneumoniae was isolated in two laboratories and on two occasions from the knee joint of a hypogammaglobulinaemic patient with a chronic polyarthritis.

Variation of cold agglutinin levels

Cold agglutinin levels were determined in 120 individuals ranging in age from 1 to 64 years using untreated and ficin-treated group O erythrocytes. The geometric mean titer for untreated cells was 5.7 +/- 1.1 SEM and for ficin-treated cells 18.7 +/- 1.1 SEM. The mean titers and scores for various blood groups were not significantly different. Titers and scores correlated significantly to total serum IgM concentration (p less than 0.001). Females had significantly higher cold agglutinin levels than males (p less than 0.001). A significant decrease of cold agglutinins occurred in the 26- to 64-year age group as compared to the 11- to 25-year age group (p less than 0.01). The data should contribute to a clearer understanding of the biological impact of cold agglutinins.

Pulmonary infection and rheumatoid arthritis

Five of eleven patients with bronchiectasis and/or cystic fibrosis developed a polyarthritis with positive tests for rheumatoid factor. Possible mechanisms of this complication are discussed.

Mycoplasma pneumoniae infections in children

Details are given of all serologically confirmed Mycoplasma pneumoniae infections in children referred to Bristol hospitals during an epidemic lasting 18 months. 44 children, many below school age, had lower respiratory infections. The majority had cough and malaise which had failed to respond to antibiotics given before referral. Chest x-rays showed no pathognomonic features: segmental or patchy consolidation was common; 3 cases of lobar consolidation. Cold agglutinins were raised in 9 out of 12 cases. In the majority of cases the total leucocyte count was normal and the absolute neutrophil count raised. Mean duration of symptoms was 4.2 weeks (range 1-16). Treatment with erythromycin or tetracycline appeared to have little effect in most cases. Seven nonrespiratory manifestations were seen in 6 children. These were meningitis (2 cases), Stevens-Johnson syndrome (4 cases, 1 case complicated by toxic epidermal necrolysis), and acute haemolytic anaemia (1 case).

Mycoplasma pneumoniae infection and arthritis in man

Seven patients developed arthritis after Mycoplasma pneumoniae infection. Their joint symptoms persisted for up to one year. One patient developed an articular erosion and in another rheumatoid factor was present in serum transiently. Mycoplasma infection often causes ill-defined arthralgias and myalgias, but the migratory polyarthropathy of middle-sized joints that occurred in these patients is much less common. The prognosis seems to be good.

Myocardial dysfunction and hemolytic anemia in a patient with Mycoplasma pneumoniae infection

A patient with evidence of myocardial abnormalities and hemolytic anemia is described, in whom the responsible pathogen appeared to be Mycoplasma pneumoniae (as indicated by a 64-fold rise in complement-fixation titers, and by a change in cold-agglutinin titers from 1:8 to 1:4,096). Both cardiac and hematologic problems occurred during the recovery phase from pneumonia and were associated with marked deterioration in the patient's clinical status. Electrocardiographic and serum enzymatic changes mimicked the patterns seen in acute myocardial infarction.

Transverse myelitis complicating Mycoplasma pneumoniae infection

A 23-year-old man developed transverse myelitis following an infection with Mycoplasma pneumoniae. Neurological complications following infection with this organism are uncommon but the prognosis appears to be good.

Pericarditis during infection with Mycoplasma pneumoniae

A 37-year-old woman was found to have pericarditis during the course of a Mycoplasma pneumoniae infection which also produced primary atypical pneumonia. Intrafamily spread of the infection was observed, with varying clinical manifestations. The case is described because there appears to be little information on mycoplasma pericarditis.

Thrombotic thrombocytopenic purpura--remission following splenectomy. Report of a case and review of the literature

A case of thrombotic thrombocytopenic purpura in which sustained remission followed splenectomy is described. Strong serologic evidence of concurrent infection with Mycoplasma pneumoniae was found in this case. Previously reported cases in which thrombotic thrombocytopenic purpura has been associated with infections are reviewed. An approach to management of this unusual and frequently fetal condition, is suggested, based on a detailed review of the recent literature.

The use of organ cultures and animal models in the study of Mycoplasma pneumoniae infections

Organ cultures of ciliated tracheal epithelium derived from various animal species have been used to study several different mycoplasma infections. Human and hamster tracheal cultures have been used in particular to study Mycoplasma pneumoniae which, of all the human mycoplasmas, is the only one which damages the cultures. One reason for this is the capacity of the virulent organisms to attach to the cells; strains which are prevented from attaching or have lost this capacity do not damage the cultures. The organ culture system is therefore valuable in looking at the organisms-cell relationship but it is necessary to use animal models to study immunological processes. Hamsters, and more recently guinea pigs, have been used in this respect. The hamster model has been used to study the pathogenesis of M. pneumoniae pneumonia and also recovery from and resistance to infection. Humoral immune mechanisms seem more important than cell-mediated mechanisms in resistance, and the probable importance of local immunity is discussed. It is pointed out that it should be possible to establish the mechanisms underlying the development of M. pneumoniae sequelae where conditions, similar to those seen in man, occur in animals. Finally, the way in which the hamster model has been used to study the effect of tetracycline and erythromycin on the course of disease is discussed. As in man, therapy often improves the pneumonia but does not eradicate the organisms. This is probably due, at least in part, to the fact that the antibiotics are only mycoplasmastatic. Drugs with mycoplasmacidal properties are needed and the animal model would obviously prove helpful in evaluating these.

Mycoplasma pneumoniae as a cause of pneumonia, lung abscess and pleural effusion: a case report

A case report of a 26 year-old asthmatic male is outlined in order to show the clinical features and unusual development pattern of pulmonary disorders and pleural effusion with a Mycoplasma pneumoniae pneumonia. A literature review is included in order to put this unusual case into perspective.

The results of pulmonary function tests in patients infected with Mycoplasma pneumoniae

A comparative study was undertaken in order to ascertain the effects of a Mycoplasma pneumoniae infection on pulmonary function. It appears that the literature has many articles devoted to the clinical symptomatology of this type of infection but there is very little information available on the abnormalities which occur in the lungs with this infection. The patients who were used as a comparative model had lung lesions which gave a similar radiographic appearance. The significant finding was that an obstructive syndrome with increased airway resistance was noted in the M.pneumoniae pneumonia patients.