Studies were carried out into the immunopathogenesis and laboratory diagnosis of dengue virus infections. Using an experimental system it was shown that cell-mediated immunity (CMI), as measured by delayed-type hypersensitivity (DTH) was induced in mice infected with dengue virus. The nature of the DTH response satisfies most criteria for a classical DTH reaction. In addition, it was also shown that infection with dengue virus causes a transient immunosuppression as measured by the immune response to other, unrelated antigens. With regard to the laboratory diagnosis of dengue infections, it was found that mosquito cells were a sensitive system for the isolation of dengue viruses and that the success of isolation was related to the antibody content of the serum. A new method for the rapid isolation of dengue viruses was also developed involving the intracerebral inoculation of mosquito larvae. By the use of this method viral antigens can be detected as early as 2-3 days after specimen inoculation. The significance of these findings in relation to the immunopathogenesis, prevention and control of disease syndromes due to dengue viruses is discussed.
Erythema Nodosum Leprosum (ENL) or Type II reaction is an immune complex syndrome seen in multibacillary leprosy. 20 patients with histological confirmation of ENL in leprosy were studied from 1982 to 1986. These patients had a range of clinical signs, from fever, tender dusky nodules, bullae, ulcers to lymphadenopathy, arthralgia and neuritis. The four major histological patterns are: a) classical pattern showing heavy infiltrations of neutrophils in three cases, b) sub-epidermal bulla pattern with marked oedema of the upper dermis, and collections of neutrophils in five cases, c) vasculitis pattern, affecting superficial and mid-dermal vessels, leading to epidermal necrosis, bulla formation and ulceration. Dilated vessels, congestion, lumenal fibrin clots and fibrinoid necrosis of vessels were seen, d) non-specific picture in nine cases with mild oedema, infiltration with neutrophils, and two cases with minimal reaction had chronic ENL with clinical vasculitis. All the five cases with vasculitis showed C1q, C3 and fibrinogen in the vessels. Comparing ENL reactions reported in Asia, our pattern is similar to that of Malaysians with the majority showing sub-epidermal oedema. Vasculitis is more common in India. Oedema with collagen necrosis as seen in acute ENL with iritis in New Guinea. The Lucio's phenomenon was not seen in any of the countries in Asia.
Immunology is a discipline that traverses all branches of clinical medicine. Thus since about ten years ago major hospitals in Malaysia established routine clinical immunology services particularly in the diagnosis of autoimmune/connective tissue disorders. More recently these laboratories have ventured into basic research in Dengue Haemorrhagic Fever, Leukaemia Immunology, Nasopharyngeal Cancer and Leprosy. The rationale for these projects together with early results from them are discussed.
A retrospective study of 84 cases of neonatal septicaemia admitted into a neonatal unit in a rural area of Malaysia for 1 year between 1st September 1985 to 31st August 1986 was carried out to determine the spectrum of micro-organisms and predisposing factors in relation to early and late onset septicaemia. The incidence of neonatal septicaemia was 2.13 per 1,000 live-births per year and the case fatality was 41.7% with higher case fatality in those who were premature, those who presented as early onset and those who had gram negative septicaemia. The mean age of onset of septicaemia was 7.8 days (range from 2 hours to 27 days). Forty four (52%) neonates had early onset septicaemia with mean age of onset at 2.7 days; forty (48%) neonates had late onset septicaemia presenting at 13.6 days of life. Gram negative organisms such as Klebsiella, Pseudomonas, sp., E. coli and Streptococcus, especially group B Streptococcus were the major organisms in the early onset septicaemia. Staphylococcus aureus and Staphylococcus epidermidis were the major organisms responsible for the late onset septicaemia. Obstetrical factors played an important role in early onset septicaemia. Prematurity was the most common predisposing factor. Invasive diagnostic and therapeutic procedures including surgery highlighted once again the importance of these procedures in predisposing the newborn to infection.
The results of speech, language and hearing assessment of repaired cleft palate children and adults over a 4-year period at the Speech/Language therapy unit, Department of ENT, Faculty of Medicine, UKM are reported. The subjects were 33 incomplete cleft lip palate (ICLP), 48 unilateral complete cleft lip and palate (UCLP) and 26 bilateral complete cleft lip and palate (BCLP). Results obtained for the following assessments are reported and discussed: (i) Hearing assessment, (ii) intelligibility rate, (iii) severity of hyper-nasality and (iv) types of articulation errors and school/behaviour problems and nasal grimace. Due to subject variability in ethnicity, language and dialects and the lack of normal data, it is difficult to compare or repeat previously reported results. Assessment of intelligibility, hypernasality and articulation were conducted using the Malay language. Results obtained were compared among the three groups of subjects. The significant findings were that hypernasality, intelligibility and articulation errors were more severe in the ICLP group than in the UCLP or BCLP groups of patients. This is contrary to expectations and cannot be explained in terms of the type and/or the degree of clefting. Hence, special attention should be paid to the less overt type of cleft patients in so far as their speech assessment and rehabilitation are concerned.
In Singapore, cancer incidence is documented separately for the different Chinese dialect groups, as a means of providing a possible insight into environmental or genetic factors which may be involved in the aetiological process. Thus, it would be useful to determine whether or not the Chinese population in Singapore still comprises distinct dialect groups. In view of this, an investigation into the dialect group of the parents of 792 hospital in-patients (cases and controls) was carried out. It was found that the vast majority of patients (94.2%), most of whom were born before 1940, had parents of the same dialect group. The percentages of within-dialect marriages were only slightly less for offspring born in Singapore or Malaysia as opposed to China, and decreases with time were small. Thus in 1985-87 Chinese cancer patients and controls in Singapore, of the ages represented in this study may indeed be classified according to their father's dialect and this is likely to be the case for at least the next decade or so. This finding will be of use to cancer epidemiologists as well as others studying Chinese dialect group variations in disease patterns.
Ten out of 237 patients who underwent renal transplantation between 1975 and October 1986 developed tuberculosis. Most patients presented with vague symptoms, and typical symptoms commonly associated with tuberculosis were not common. Six had positive urine cultures. One patient had positive sputum and urine cultures and one had positive sputum and cerebrospinal fluid cultures for tuberculosis. In this last patient cryptococcus was also cultured from the sputum and CSF. Nine of the 10 patients responded well to antituberculosis therapy and was cured of the infection. The patient with associated cryptococcal infection died 2 months after presentation. Side effects of antituberculous therapy was minimal and easily resolved on stopping the offending drug.
410 cases of psoriasis [282 males (68%) and 127 females (31%)] were interviewed and examined to study the nail changes. The prevalence of nail changes was 78.0% (males = females). Common changes were pitting (67.5%) and onycholysis (67.2%). Dystrophy of varying degrees occurred in 35.0%, subungual hyperkeratosis in 24.7%, discoloration in 18.4%, loss of nails in 2.8% and pustulation in 1.3%. Pitting and onycholysis was the most common combination (45.6%). Nail changes were significantly more common in patients who have moderate to severe psoriasis as compared with patients with mild psoriasis; in patients who have psoriasis for greater than 5 years as compared with patients who have psoriasis for less than 5 years; and in patients older than age 50 as compared with those aged less than 50. A definite correlation was found between the prevalence of nail changes and the presence of scalp and periungual psoriasis, and the presence of joint involvement.
Forty-five Asian patients (Indians 35, Chinese 8, Malay 2) with histologically proven lichen planus were studied by immunofluorescence. The most characteristic feature, seen in 93% of the cases, was shaggy deposition of fibrinogen along the basement membrane. Immunoglobulin deposition along the basement membrane was notably, absent. Colloid bodies were observed in 87% of the cases. Fibrinogen was the most common immunoreactant, and its presence in colloid bodies was always associated with fibrinogen deposition along the basement membrane zone. Colloid bodies also contained a variety of other immunoreactants. However, staining for IgM was noted to be the most intense. The combination of shaggy deposition of fibrinogen along the basement membrane, in the absence of immunoglobulins, and the presence of colloid bodies around the basement membrane zone, is highly characteristic of lichen planus. The pattern of immunofluorescence among Asians with lichen planus, conforms to that observed in other races. There did not appear to be any difference in the immunofluorescence staining with pattern in the three racial groups studied.
Congo red screening of tissue blocks from 37 consecutive autopsies on leprosy patients revealed 7 cases of systemic amyloidosis, indicating a prevalence rate of 19%. 5 were males and 2 females. All were ethnic Chinese. Their ages ranged from 52 to 85 years with a mean of 69 years. Six had lepromatous leprosy while the remaining 1 had tuberculoid leprosy. In all 7 cases, the amyloid was AA in type, being permanganate-sensitive and immunoreactive with anti-human AA protein antiserum. Hepatic deposition was limited to blood vessels, a pattern typical of AA (secondary) amyloidosis. With regard to renal involvement, 4 showed a predominantly vascular pattern of infiltration while 3 exhibited the more ominous glomerular pattern. Three died of chronic renal failure and 2 of congestive cardiac failure attributable to renal and cardiac amyloidosis respectively. One patient succumbed to septicaemia and the remaining 1 to acute myocardial infarction. AA amyloidosis remains a serious and significant complication of leprosy among Malaysians.
An analysis of cutaneous amyloidosis cases during a five year period, from January 1, 1983 to December 31, 1987, showed that of 78 cases suffering from lichen amyloidosis, 9 patients (11.5%) were male and 71 patients (80.5%) female. Macular skin amyloidosis was observed. Sixty patients (76.9%) were found in the age range of 20-50 years. Forty-nine patients (62.8%) suffered from the disease for 2 years or less. Skin changes were mainly located on the shin areas, the posterior part of the lower thighs and posterior part of the forearms. Treatment with strong topical corticosteroids and keratolytic agents (salicylic acid ointment in higher than 3%) proved to be unsatisfactory. The literature mentions higher incidence of lichen amyloidosis in Chinese, Malaysians and Indonesians than in Caucasians.
One hundred years ago cervical cancer was rapidly fatal, regardless of therapy rendered. Today with cytological screening, early diagnosis is possible and ablative therapy can be instituted in appropriate cases. The advent of coloscopy has helped reduce unnecessary cone biopsy for diagnosis. However, the same cannot be said of the use of cytology for screening endometrial cancer, and often endometrial tissue biopsy is necessary. Ovarian cancer is notoriously silent in its early stages and symptoms if present are generally non-specific. To date there is no other useful and reliable method for its early detection than routine pelvic examination. An annual cytological screening test for cervical cancer will give an opportunity for examination of the breasts, abdomen and pelvis. Screening techniques for female genital tract malignancies are discussed.
This is a retrospective study of 525 posterior chamber implants in diabetics performed by A S M Lim and B C Ang of Singapore. The patients were reviewed by visiting ophthalmologists--J E Kennedy (Sydney), M Ngui (East Malaysia) and P M Hart (Belfast). This study did not show any significant difference in the complication of post-operative visual acuity between diabetics and non-diabetics. 95% obtained 6/12 vision or better when pre-existing disease was excluded. It also showed that posterior chamber implants can be inserted in eyes with maculopathy or proliferative retinopathy if laser treatment was effectively done before or after surgery.
Mortality from ischaemic heart disease in Singapore is now reaching comparability with the West. For the early 1980s, rates for Indians and Malays were higher than in U.S.A. and England and Wales and while those for Chinese were lower they were considerably higher than in Japan. In keeping with this the levels of the major risk factors in Singapore are now comparable to the West. Cigarette smoking in males is virtually the same as in Britain, while the proportion of hypertensives on medication is higher than in the West. The main cause for concern is the current high levels of serum cholesterol in Singapore and strenuous health education efforts are needed to bring about dietary changes.
Based on data collected by the population-based Singapore Cancer Registry over the period 1968 to 1982, baseline epidemiological characteristics and incidence trends of primary liver cancer were described. This will facilitate the interpretation of future trends, especially in the light of new interventions such as hepatitis B immunisation. The primary liver cancer incidence is four times higher in males than in females, with the incidence peaked in the seventh decade. The incidence rate was higher in the Chinese than in Malays and Indians and marginally higher among foreign born than Singapore born Chinese. A general declining trend in liver cancer incidence was especially notable in the local born Chinese. Misclassification of metastatic carcinomas in the earlier years of cancer registration may have contributed to the initial higher incidence. Definitive decrease in incidence as a result of hepatitis immunisation will only be seen in another two to three decades.
The effect of alteration of eating pattern during Ramadan on body mass index (BMI), serum fructosamine: total protein ratio (F/TP), and glucose level in 18 healthy male Asiatic Moslems were studied. The results showed a significant decrease (p less than 0.025) in F/TP at the second week of Ramadan in 11 subjects who experienced continuous decrease in BMI throughout Ramadan. The remaining 7 subjects showed no significant changes in BMI and F/TP. No evidence of hypoglycaemia was observed in the subjects during the study. Serum fructosamine: total protein ratio in subjects with altered eating pattern preferably should be interpreted along with the change in body mass index.
A rapid method of assay, using a monoclonal antibody linked to alkaline phosphatase, was used for the detection of the Pontiac subgroup of Legionella pneumophila serogroup 1. It was tested for its specificity against 53 strains of Legionella recently isolated from the environment in Singapore and Malaysia. The specificity and sensitivity of this method of assay was confirmed, though there is some concern that the specificity was too narrow, and there are reservations about the criteria suggested for interpreting the results.
The present study analysed the records of 342 elderly subjects aged 55 years and above of different ethnic groups to ascertain the types and level of their unperceived dental needs. The overall percentage of unperceived needs was highest among the Malays (96.1% or 74/77 subjects) and among the men (88.5% or 139/157 subjects). The unperceived need for prosthetic treatment was highest among the Malays and Chinese as well as among women, whereas the unperceived need for treatment for periodontal disease was highest among the Indians. The data for unperceived needs for prosthetic treatment as well as for treatment for caries and periodontal disease were somewhat similar among men. Within each ethnic group, variations among sex in the unperceived needs for the various dental symptoms were also noticeable. Further research is indicated to ascertain the role of traditional and cultural concepts and dogmas in determining the importance attached to the various dental health symptoms within each ethnic group.
The prevalence and symmetrical distribution of enamel defects were studied in 218 Malaysian school children aged 11-12 years old. The tooth prevalence of enamel defect was 40.3 per cent. The first permanent molars were the most severely affected, whereas the lower incisors were the least severely affected. Overall there was no sex difference. Distribution of symmetry was assessed between the right and left tooth pairs as well as for upper and lower teeth. A higher proportion of symmetry was observed for the right and left tooth pairs and the lingual surfaces showed a greater percentage of bilateral distribution.
The aim of this study is to determine the social impact of oral and facial pain in a sample involving an industrial population. Out of a total of 355 subjects interviewed, nearly one-half claimed to have oral and facial pain in the previous one month prior to the survey. The most common type of pain was that related to hot or cold fluids or sweet things followed by toothache. On the average, the pain lasted for 4.2 days (SD = 4.9) per person in the past one-month. About one in five persons with pain reported that it was severe enough to disrupt sleep. About one in ten persons reporting pain had to take sick leave because of the pain. However, only one in four persons with pain consulted a doctor or dentist. More than one-third tried to cope with the pain and did nothing while the rest tried various means of self-cure. It is therefore postulated that in this population, pain per se is a poor predictor of utilisation of dental services. Further research into pain coping behaviour and how this affects of pattern of utilisation of dental services is indicated in order to formulate a strategy to encourage the habit of seeking prompt dental care by the target population.