The Epstein-Barr virus (EBV), traditionally linked etiologically with infectious mononucleosis (IM), endemic Burkitt lymphoma (BL) and nasopharyngeal carcinoma (NPC) has in recent years been associated with a host of other conditions. Viral strategies for entry into cells and persistence, as well as various molecular mechanisms involved in latency, replication and transformation have been elucidated. EBV termini analysis has demonstrated the essentially clonal nature of BL, NPC and preneoplastic lesions of the nasopharynx. Strain variation between isolates of EBV suggests that differences in epithelial cell tropism among strains may exist. Treatment of EBV-associated syndromes is largely supportive although antivirals may play a role in the management of oral hairy leukoplakia. At the present time, the development of an effective vaccine remains a viable proposition.
Schistosomiasis was discovered in Malaysia in 1975 in an autopsy case. Since 1975 autopsies, surveys, and resurveys have been carried out to identify animal hosts, snail intermediate hosts, and reservoir hosts. Seroepidemiologic tests involving enzyme-linked immunosorbent and circumoval precipitin methods have been used to determine the true incidence and prevalence of this protean disease among the Orang Aslis (aborigines) in Malaysia. With the use of better epidemiologic and parasitologic tools, more cases of schistosomiasis are being reported.
Peripheral neuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes are often the presenting features of the POEMS syndrome. Approximately 50% of these are associated with osteosclerotic myeloma, a rare variant of multiple myeloma and some with Castleman's disease, an unusual lympho-proliferative disorder. The underlying pathogenetic mechanisms have not been elucidated but amelioration of symptoms with the disappearance of the M-component suggests possible etiopathogenic mechanisms. We present a 40-year-old woman with manifestations of all three disorders.
Between January 1974 and June 1980, 85 cases of cryptococcosis were diagnosed in the University Hospital, Kuala Lumpur, Malaysia. The diagnosis was based on positive culture of the organism in 81 cases; the remaining four were diagnosed on histopathological findings. Cerebral cryptococcosis was the most common presentation and Chinese are particularly susceptible (72% of cases). The incidence of the disease is shown to be far greater than previously suspected. Association with compromised host status is uncommon (14%). The local literature is briefly reviewed and the findings discussed.
A rare case of squamous cell carcinoma diagnosed in early pregnancy in a 28-year-old woman is described. At the time of radical surgery, which was carried out in the puerperium, the growth had already advanced to Stage IV disease. The rapid growth of the tumor seen in this patient suggests that although treatment needs to be individualised, the definitive radical surgery should not be delayed.
Three cases of muscular sarcocystosis from West Malaysia are reported. The morphological features of the parasites from these three cases are similar to the eight cases previously reported from this country. A review of this total of eleven cases of muscular sarcocystosis showed that they were all incidental findings, where man acted as intermediate hosts of as yet unknown Sarcocystis spp. These cases of muscular sarcocystosis were probably zoonotic in origin and associated with close contact with definitive hosts (both domestic and wild animals) thus permitting the contamination of food and drink with sporocysts shed by these definitive hosts. These infections were probably acquired locally as most of the subjects were born in Malaysia and none had ever left the country to stay elsewhere. Eight of the eleven cases reported were associated with malignancies, especially of the tongue and nasopharynx.
BACKGROUND: The diverse range of diseases that affect the salivary glands may lead to problems and pitfalls in cyto-diagnosis. While false negative diagnosis of cystic salivary gland tumors is well known, false positive cytodiagnosis in nonneoplastic salivary cysts is less well documented.
CASE: An 85-year-old female presented with a painless left parotid gland swelling of three months' duration. Fine needle aspiration cytology yielded fluid, smears of which showed keratinizing squamous cells with nuclear atypia leading to a cytologic diagnosis of cystic squamous cell carcinoma. A total radical parotidectomy followed. Histopathologic study showed cystic dilatation of many of the salivary ducts, which were lined with metaplastic squamous epithelium that showed atypia. There was no evidence of squamous cell carcinoma.
CONCLUSION: Squamous metaplasia is known to occur in benign salivary gland lesions, such as pleomorphic adenoma and Warthin's tumors, as well as in salivary duct cysts and necrotizing sialometaplasia. However, atypical squamous metaplasia of salivary duct cysts mimicking squamous cell carcinoma on cytology is unusual.
Two groups of three rabbits each were infected with 250 cercariae of the Baling and Koyan strain of Schistosoma malayensis. Changes induced by both strains included periportal hepatocellular necrosis and fibrosis. Vascular changes such as portal phlebitis and thrombophlebitis and varying degrees of pericholangitis were also present. Amyloid deposition was noted. A comparative study of the changes induced in rabbits by S. malayensis, S. mekongi and S. japonicum showed that the hepatic lesions induced by the Baling strain of S. malayensis were similar to that induced by S. japonicum, and were more severe than that induced by S. mekongi or the Koyan strain.
Schistosoma malayensis Sp N is a putative new species of schistosome discovered in Peninsular Malaysia in 1973. This paper comprises the first report on the detailed gastrointestinal pathology present in rabbits infected with strains of the parasite. Two different strains of schistosome--the Baling and Koyan strains--from two different ecosystems were used to infect inbred rabbits and the resulting pathophysiology was studied. Our results showed that the Baling strain of S. malayensis was more virulent than the Koyan strain and produced nodular, segmental circumferential lesions and large bilharziomas measuring 1-7 cm in diameter in the distal jejunum, ileum and the ileo-caecal junction. The findings indicate that the Baling strain of S. malayensis was more pathogenic for rabbits as compared with the Koyan strain--in relation to the gross pathology of the gut and the tissue egg load. Earlier reports have shown that rabbits infected with S. japonicum induces significant intestinal lesions in rabbits (Cheever et al, 1980 a,b) but these animals are refractory to infection with S. mekongi (Byram and Lichtenberg, 1980). Our studies show that the two strains of S. malayensis adapted well in rabbits. It is also established that in rabbits, the virulence of the Baling strain of S. malayensis is greater than that of S. mekongi and approximates that of S. japonicum.
Comment on: Teoh MK, Chong JM, Mohamed J, Phang KS. Protection by tocotrienols against hypercholesterolaemia and atheroma. Med J Malaysia. 1994 Sep;49(3):255-62
Two distinct strains of Schistosoma malayensis exist in Malaysia (designated the Baling and Koyan strains). Both these strains show intraspecific variations in pathology (Greer et al, 1988). To evaluate the differences in the pulmonary pathology resulting from infections of the two different strains of Malaysian schistosome, a total of 20 experimental rabbits were infected, 10 each with cercariae of the Koyan strains. Pathological changes were studied over a period of 28 weeks. Granulomas in the lung occurring as a result of infection with the Baling strain were compared with those caused by infection with the Koyan strain. Although both strains produced parenchymatous and alveolar lesions, granulomas caused by the Baling strain of Malaysian schistosome were more numerous and larger (when comparing mean diameter as well as area of granuloma, p < 0.05). In addition, pulmonary vascular hypertensive changes were present in Baling strain infected rabbits. These comprised of pulmonary arteriolar endothelial swelling and damage, intimal elastosis and medial hypertrophy. Angiitis and pulmonary periphlebitis were also noted occasionally. In contrast, Koyan strain infection resulted in fewer and smaller granulomas. Pulmonary vascular changes were minimal.
The prevalence of human skeletal muscle sarcocystosis in Malaysia was determined by serial examination of formalin-fixed, paraffin-embedded sections of tongue tissues obtained from consecutive, routine autopsies of subjects aged 12 years or more. Of 100 tongues examined, 21% were found to contain Sarcocystis; 66 cysts were found. The number of cysts per case varied from 1 to 13. In one case, 5 cysts were found in a single tissue section. The age range of positive cases was from 16 to 57 years (mean 37.7 years). Prevalence did not differ with regard to race, sex or occupation. The prevalence of human muscular sarcocystosis in our study was higher than that reported elsewhere. Preferential localization of Sarcocystis in tongue or head and neck and/or genuinely high prevalence in south-east Asia are possible explanations for this observation.
Amiodarone, a commonly used antiarrhythmic agent, has numerous adverse effects. The purpose of this case report is to highlight its hepatotoxicity, an unusual complication of long term amiodarone therapy. Our patient is a 76-year-old man with underlying ischaemic heart disease and recurrent ventricular tachycardia. Eleven months after commencing amiodarone, he developed asymptomatic raised aminotransferases which resolved following drug withdrawal. Amiodarone was then reintroduced and four years later, the patient developed hepatomegaly, worsening liver biochemistry and histopathological changes consistent with early cirrhosis. His symptoms improved following discontinuation of amiodarone. However, hepatomegaly and a low serum albumin still persist four years later.
The first two cases of human muscular sarcocystosis are reported from East Malaysia, in Sabalt and Sarawak respectively. Sarcocysts were seen iin biopsied specimen from the nasopharynx of both patients who had carcinoma of the nasopharynx. The measurements and appearances of the cysts and the zoites within the cysts were compared with the human cases of sarcocystosis previously reported in West Malaysia. Zoonotic and other aspects of these cases of East Malaysian sarcocystosis are discussed.
A retrospective study of 1000 cases of microscopically diagnosed head and neck cancers in the University Hospital, Kuala Lumpur was done. Head and neck neoplasms comprise 7.1% of all tumours diagnosed in this Hospital and the commonest sites of involvement are the nasopharynx (29.1%), cervical lymph nodes (22.6%), oral cavity (10.2%), thyroid (8.2%) and skin (6.5%). Histologically, 87% of tumours are epithelial in nature. The results of this study show that nasopharyngeal carcinoma is commonest in Chinese males, while oral and laryngeal malignancies occur more frequently in Indians.
The ultrastructure of the human skeletal muscle sarcocyst found in Malaysia is reported. Sarcocyst-positive, formalin-fixed tongue tissues were postfixed in osmium tetroxide. The primary cyst wall consisted of a thin membrane supported by osmiophilic material that was interrupted regularly by vesicle-like invaginations. Although there were no cytophaneres, stubby protrusions of the primary wall were observed. These protrusions were accentuated by dense, curvilinear material externally. The primary wall was wavy over about half the cross section of the cyst. The granular ground substance underlying the primary wall occasionally contained hitherto undescribed coiled microtubular structures. Branching septa extended from the ground substance into the cyst, separating mature merozoites into compartments. A few peripheral metrocytes and many laminated myelin figure-like structures, probably degenerating merozoites, were found. Although the human muscular sarcocyst has the same basic ultrastructure as those found in other animals, the stubby protrusions and coiled microtubular structures in the ground substance have not been described previously in nonhuman animals.
Behçet's syndrome is a rare multisystem disorder. The occurrence in families although well recognised is uncommon. The mode of inheritance, however, has not been elucidated. Sixty-one cases of familial disease have been documented to date. There was only one previous report on familial Behçet's syndrome with gastrointestinal involvement. This paper reports two cases of Behçet's syndrome with gastrointestinal involvement in a Malaysian woman of Chinese ethnic origin and her child. The mother satisfied three major criteria (oral ulcers, genital ulcers and erythema nodosum) and one minor criterion (gastrointestinal involvement). Her son satisfied two major criteria (oral and genital ulcers) and three minor criteria (intestinal involvement, central nervous manifestation and a positive family history). The radiological and pathological features of the gastrointestinal lesions in both patients resembled those of Crohn's disease. The literature on Behçet's syndrome is reviewed.