Non-specific aorto-arteritis in Singapore with special reference to hypertension.

Aorto-arteritis has recently emerged as a distinct disease entity with involvement of aorta and its major branches by a non-specific inflammation of unknown etiology. Though the distribution of this disease is worldwide, it is more prevalent in Japan, India, and South-east Asia. This paper describes a series of 48 cases seen in Singapore and emphasizes the protean nature of this disease. Though modes of clinical presentation were many, hypertension appeared to be the commonest as it occurred in 33 patients, giving an incidence of 69 per cent. This incidence was much higher than the 48 per cent reported among Europeans and 42 per cent reported among South Africans. It would therefore appear that hypertension was a far more common manifestation of aorto-arteritis among Asians. The commonest cause of hypertension in aorto-arteritis in this series was renovascular, with renal artery stenosis or occlusion occurring in 27 cases (85 per cent). The frequency of involvement of the renal artery is much greater than the 34 per cent reported by the Japanese. Therefore renovascular hypertension should be regarded as a predominant feature of aorto-arteritis in Singapore.     

Complications in tuberculous patients--with special reference to secondary mixed infections

An attempt was made to elucidate the mechanism which makes pulmonary tuberculosis intractable. Patients with pulmonary tuberculosis were divided into the following two groups; one group consisted of patients (n = 37) in which tubercle bacilli converted to negative within 6 months after the institution of anti-tuberculous chemotherapy and remained negative thereafter, and the other group (n = 21) in which tubercle bacilli persisted in spite of long-term chemotherapy. A comparison was made on serum factors and blood cell components, which were linked with humoral and cellular immunity respectively, between the above two groups of tuberculosis patients. As the result, reductions was observed in the ratio of serum albumin to globulin and increase in erythrocytes sedimentation rate and in amount of immunosuppressive acidic proteins in the chronic bacillary cases as compared with the patients in which negative conversion of bacilli had been achieved. A depressed cellular immunity was also found in the former group of the patients as evidenced with the reduction in a ratio of helper/inducer T lymphocytes to suppressor/cytotoxic T lymphocytes and in intensity of skin reaction to PPD. The depressed humoral and cellular immunity observed in chronic bacillary cases were one of possible causes of intractability of the disease and also the major cause of the frequent involvement with pulmonary infections with pathogens other than tubercle bacilli. At the second part, a problem in treating patients with both lung cancer and pulmonary tuberculosis was discussed, since iatrogenic immunosuppression was induced almost unavoidably by the use of anticancer agents.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dilated cardiomyopathy with special reference to humoral immunity.

The question of whether the etiology of DCM is immune or autoimmune has been increasingly discussed. Abnormal findings on humoral immunity in DCM were investigated, especially those regarding anti-heart antibodies (AHA), IgG subclasses and soluble interleukin-2 receptor (sIL-2R). The heterophile type AHA was detected in 64.7% of cases by the indirect immunofluorescence technique (IF) with rat heart, by indirect IF with human heart AHA in 57.8% of cases, and by thin-layer chromatogram with human glycolipids AHA in 44% of cases. Also, 57.1% of the specimens were found to bind IgG on perimyocytes by direct IF with biopsy specimens taken from patients with DCM. The epitope of an antigen which reacted with the heterophile type AHA is a Gal alpha 1-3Gal structure. 200 Kd, 70 Kd and 40 Kd antigens were reacted with AHA detected by indirect IF with human heart. The possible mechanisms of AHA in the pathogenesis could be either complement dependent cytotoxicity or interference to cardiac metabolism. The concentration of sIL-2R and IgG3 in sera from patients with DCM were elevated. These results suggest that immunological abnormalities occur continuously in DCM.     

Clinical observations on lower respiratory tract infections with special reference to serum IgE levels

To examine if the occurrence of wheezing among children with lower respiratory tract infections is associated with atopic predisposition, serum levels of IgE were determined for groups of children with or without wheezing, during infection with Mycoplasma pneumoniae or respiratory syncytial virus (RSV). In M. pneumoniae infection, more than 60% of wheezy children over 2 years of age showed a high IgE level (200 IU/mL or more), while IgE levels were less than 200 IU/mL in 73% of non-wheezy children. In RSV infection, the incidence of high IgE levels among wheezy children was nearly double that of non-wheezy children, although the difference was not significant. These results suggest that in children an allergic disposition is involved in the occurrence of wheezing during the course of lower respiratory tract infections.     

Pneumonia and pneumococcal infections, with special reference to pneumococcal pneumonia. The 1979 J. Burns Amberson lecture.

An etiologic classification of acute pneumonia was presented and the relative importance of some of the causative agents was briefly reviewed. The early developments of the therapy of pneumococcal pneumonia with type-specific antisera, sulfonamide drugs, and antimicrobial drugs were reviewed, mostly from the experiences of the author at Boston City Hospital. Changes in the occurrence and relative importance of the pneumococcus as a cause of infections associated with bacteremia, empyema, and meningitis were demonstrated, based on cases observed at Boston City Hospital during 12 selected years between 1935 and 1972. These findings, among others, indicate that the pneumococcus is still one of the most important causes of serious bacterial infections and of mortality from such infections, particularly in the elderly. Some possible indications for polyvalent pneumococcal capsular polysaccharide vaccine were discussed, and the need for further extensive clinical and field trials to demonstrate its range of effectiveness was stressed.