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S de Silva

Publications and source records attributed to S de Silva.

At least 19 recordsLinked to original sources
PubMed2006

Survey of HIV and hepatitis B or C co-infection management in the UK 2004.

The objective of this study is to evaluate the current management practices of patients with HIV and hepatitis B or C co-infection. A postal survey was made of 186 clinics in the UK between October 2003 and January 2004. In total, 100/186 (54%) clinics responded: 16% estimated their hepatitis B prevalence to be above 10%, 27% estimated their hepatitis C to be above 10%. Problems were identified in a minority of clinics including: not routinely screening HIV-positive patients for hepatitis C (6%), restrictions on diagnostic tests required for the management of hepatitis infection and offering inappropriate treatment for hepatitis B infection. The use of diagnostic liver biopsies varied and clinics reported restrictions on access to hepatitis C therapy, with a consequent impact on waiting times. In conclusion, we identified several areas of concern in the diagnosis and management of HIV/hepatitis co-infection in several UK HIV treatment centres.

Antiviral Agents↗
PubMed2002

Chronic Strongyloides stercoralis infection in Laotian immigrants and refugees 7-20 years after resettlement in Australia.

During the period 1974-91 large numbers of Southeast Asian immigrants and refugees were resettled in Western countries, including Australia. Health screening during this period demonstrated that intestinal parasite infections were common. A cross-sectional survey of 95 Laotian settlers who arrived in Australia on average 12 years prior to the study was conducted to determine if chronic intestinal parasite infections were prevalent in this group. Twenty-three participants had positive Strongyloides stercoralis test results (22 with positive serology, including I with S. stercoralis larvae detected in faeces and another with larvae and equivocal serology). Of these 23 participants, 18 (78%) had an elevated eosinophil count. Two patients had eggs of Opisthorchis spp. identified by faecal microscopy. The detection of chronic strongyloidiasis in Laotian settlers is a concern because of the potential serious morbidity associated with this pathogen.

Adolescent↗
PubMed2001

Genetic determinants of jaundice and gallstones in haemoglobin E beta thalassaemia.

Chronic hyperbilirubinaemia, gallstone formation, and gall bladder disease are unusually common in people with haemoglobin E beta thalassaemia in Sri Lanka. To determine whether this has a genetic basis we compared the bilirubin levels and frequency of gallstones in patients with different alleles of the UGT*1 gene. There was a significantly higher bilirubin level in those with the 7/7 genotypes compared with 6/6 and 6/7 genotype (p=0.032 and 0.0015 respectively), who also appeared more prone to gallstone formation. These results suggest that the UGT*1 genotpe is of importance in the genesis of gallstones in this population of patients.

Alleles↗
PubMed2001

A preliminary study of the impact of long-term psychotic disorder on patients' families.

OBJECTIVE: To assess impact of long term psychotic disorders on caregivers. DESIGN: A questionnaire based, interviewer administered, cross-sectional survey using the translated version of a Burden Assessment scale (BAS). SETTING: Outpatient clinic of the University Psychiatry Unit, National Hospital, Sri Lanka. SAMPLE: 50 caregivers of patients suffering from psychotic disorders for more than 2 years. MEASUREMENTS: The BAS was administered to 50 caregivers to assess degree of distress and domains of concerns. RESULTS: 60% of caregivers felt very anxious and depressed. 54% experienced a financial decline, and 82% felt responsible for meeting the entire financial needs of the patient. 54% felt that their workload increased due to the illness. 58% of the caregivers were parents. CONCLUSIONS: Caregivers of patients with long term psychotic disorders are distressed, and have several concerns. Interventions focused on these will relieve the distress of caregivers and help patients. A majority of caregivers are parents. This has future implications, as many patients are not capable of independent living.

Caregivers↗
PubMed2001

Management of men with a first episode of acute urinary retention due to benign prostatic enlargement.

OBJECTIVE: To determine the effect of the existing management protocol of patients presenting with acute urinary retention due to benign prostatic enlargement on clinical efficacy and surgical practice. DESIGN: Prospective study. SETTING: The Urology Unit at the Teaching Hospital, Karapitiya, Galle. PATIENTS: 100 consecutive patients with a first episode of acute urinary retention due to a clinically benign enlarged prostate. MEASUREMENTS: Success of voiding urine after one week of treatment with an alpha adrenoceptor blocker (prazosin). Incidence of subsequent urinary retention during the follow up period of 6 months despite continuing treatment with the drug. RESULTS: Of the 94 patients who completed the follow up period of 6 months, 56 voided successfully after the initial trial without catheter at one week. However, 12 of them developed urinary retention during the follow up and required surgery. CONCLUSION: Treatment with an alpha adrenoceptor blocker followed by a single trial without catheter can avoid prostatic surgery in 40% of patients with acute urinary retention due to benign prostatic enlargement.

Adrenergic alpha-Antagonists↗
PubMed2000

Thalassaemia in Sri Lanka: implications for the future health burden of Asian populations. Sri Lanka Thalassaemia Study Group.

BACKGROUND: Thalassaemias pose an increasing problem for the Indian subcontinent and many Asian countries. We analysed the different types of thalassaemia in the Sri Lankan population, surveyed gene frequencies in schoolchildren, and estimated the burden of disease and requirements for its control. METHODS: We analysed blood samples from patients attending clinics in nine hospitals and defined the different types of beta thalassaemia by high-performance liquid chromatography (HPLC) and DNA analysis. The range of mutations was obtained by analysis of beta-globin genes. Capillary blood was obtained from schoolchildren from different parts of the island and analysed by HPLC to provide an approximate assessment of the carrier frequency of beta thalassaemia and haemoglobin E (HbE). To estimate the frequency of alpha thalassaemia the alpha-globin genotypes were also analysed when it was possible. FINDINGS: Blood samples were obtained from 703 patients with beta thalassaemia and from 1600 schoolchildren. The thalassaemia mutations were unevenly spread. Although 23 different beta-thalassaemia mutations were found, three accounted for the thalassaemia phenotype in about 70% of the patients, most whom are homozygotes or compound heterozygotes for IVS1-5 (G-->C) or IVS1-1 (G-->A). The third common mutation, codon 26 (G-->A), which produces HbE, interacts with one or other of these mutations to produce HbE/beta thalassaemia; this comprises 13.0-30.9% of cases in the main centres. Samples from 472 patients were analysed to determine the alpha-globin genotype. Overall, 15.5% patients were carriers for deletion forms of alpha+ thalassaemia. Average gene frequencies showed that there will be more than 2000 patients requiring treatment at any one time, in the future, of whom those with HbE/beta thalassaemia will account for about 40%. INTERPRETATION: In Sri Lanka, interactions of the two common beta-thalassaemia alleles will nearly always result in a transfusion-dependent disorder. However, about 40% of patients will have HbE/beta thalassaemia, which has a variable course. The management of these disorders could require about 5% of the total health budget. We need to learn more about the natural history and appropriate management of HbE/beta thalassaemia if resources are to be used effectively.

Adult↗
PubMed1998

A DNA probe for the detection and identification of Bacillus sporothermodurans using the 16S-23S rDNA spacer region and phylogenetic analysis of some field isolates of Bacillus which form highly heat resistant spores.

The spacer regions between the 16S and 23S rRNA genes (spacer regions 1) of Bacillus sporothermodurans were PCR-amplified, cloned and sequenced. Six unique spacer sequences in four size classes were recovered from two strains, rrnA (about 190 bp), rrnB (about 303 bp), rrnC (355 bp) and rrnD (554 bp). rrnD contained two tRNA genes which were deciphered as tRNA(ala) and tRNA(ile) separated from each other by 13 nucleotides. The primary structures of the tRNA molecules clearly resembled those found in Bacillus subtilis; the tRNA(ala) genes were identical and the tRNA(ile) genes were 95% similar. The mixed rrnA and rrnB spacers when PCR-amplified from chromosomal DNA were effective as a hybridization probe for identification of B. sporothermodurans strains. However, high background signals with DNA from some other bacilli were encountered. A more discriminating probe was prepared from the cloned rrnB spacer region. Of eight aerobic, endospore-forming bacteria isolated from silage following heat enrichment, one was identified as B. sporothermodurans using the probe and its identity was confirmed from partial 16S rDNA analysis (phylotyping). This indicated that contamination in milk and dairies by B. sporothermodurans could originate from cattle feeds such as silage. Of the other seven silage strains, only two were identified conclusively by phylotyping and three represented probable new species. The latter three strains were subjected to phylogenetic analysis using almost complete 16S rDNA sequences. Branch lengths, bootstrap percentage values, and 16S rDNA similarity to other Bacillus species suggested that these isolates are likely to constitute new species within the genus Bacillus.

Animals↗
PubMed1993

Child homicide--the extreme of child abuse.

OBJECTIVE: To review cases of fatal child abuse, looking for any characteristic features of these cases. DESIGN AND SETTING: A case review of all childhood deaths at The Children's Hospital, Camperdown, between January 1976 and December 1990. Cases with a definite diagnosis of child abuse were extracted. Cases where there was only a suspicion of child abuse as the cause of death were not included. SUBJECTS: Seventeen cases of fatal child abuse were reviewed with emphasis on autopsy findings and sociological data. RESULTS: All children who died were less than three years of age; nine were under one year. Seventy-six per cent died from head injury and 24% from asphyxia or strangulation. In addition to their fatal injuries, 41% had multiple bruises on the trunk and limbs. Thirty-five per cent had evidence of previous physical abuse. CONCLUSIONS: The commonest age for fatal child abuse is the first year of life. When physical abuse occurs in children under three years, and particularly under one year, a thorough assessment, follow-up and institution of appropriate supportive services are essential, as the abuse may be an early warning of a subsequent fatal episode of abuse. The introduction of a process of review of child deaths may increase awareness of and help prevent fatal child abuse.

Airway Obstruction↗
PubMed1992

Girls' identity formation in the changing social structure of Sri Lanka.

Adolescent girls (N = 118) from diverse social backgrounds in Sri Lanka described their views of womanhood. Qualities of the ideal woman considered most important were kindness and honesty, liking children, intelligence, and having a good job. Although the traditional role of the Sri Lankan woman is that of homemaker, most girls in the study (55%) drew the ideal woman working outside the home, often as a teacher or a doctor. Nevertheless, adolescent girls emphasized traditional qualities of the woman at both work and home as self-sacrificing and serving others.

Adolescent↗
PubMed1988

Treatment of experimental myasthenia gravis with total lymphoid irradiation.

Total lymphoid irradiation (TLI) has been reported to be effective in the immunosuppressive treatment of certain human and experimental autoimmune disorders. We have investigated the effects of TLI in Lewis rats with experimental autoimmune myasthenia gravis (EAMG) produced by immunization with purified torpedo acetylcholine receptor (AChR). The radiation is given in 17 divided fractions of 200 rad each, and nonlymphoid tissues are protected by lead shielding. This technique suppresses the immune system, while minimizing side effects, and permits the repopulation of the immune system by the patient's own bone marrow cells. Our results show that TLI treatment completely prevented the primary antibody response to immunization with torpedo AChR, it rapidly abolished the ongoing antibody response in established EAMG, and it suppressed the secondary (anamnestic) response to a boost of AChR. No EAMG animals died during TLI treatment, compared with six control animals that died of EAMG. TLI produces powerful and prompt immunosuppression and may eventually prove useful in the treatment of refractory human myasthenia gravis.

Animals↗
PubMed1977

Giant duodenal hamartoma consisting mainly of Brunner's glands.

A successfully treated case of a duodenal hamartoma is presented. A review of the literature has shown that this is the largest such tumor so far described, and the first time a mass was palpable on abdominal examination. Its large size resulted in pyloric obstruction, and its wide attachment to the duodenum necessitated a Polya-type partial gastrectomy during its removal. The pathologic controversy which has led to the classification of these Brunner's gland proliferations as duodenal hamartomas is briefly presented.

Brunner Glands↗
PubMedDate not supplied

Total lymphoid irradiation and antigen-specific tolerance: future therapy for experimental myasthenia gravis?

Total lymphoid irradiation (TLI) is effective in the immunosuppressive treatment of human and experimental autoimmune disorders, including experimental autoimmune myasthenia gravis (EAMG). Under certain circumstances. TLI may facilitate the induction of specific tolerance to antigens present during or shortly after the TLI treatment. This study was designed to determine whether TLI could induce or enhance tolerance to acetylcholine receptor (AChR), the antigen in myasthenia gravis, or to other antigens. We presented the antigens in various potentially tolerogenic forms to rats that were first pre-treated with TLI, or controls treated with sham irradiation. Injection of deaggregated human gamma globulin (HGG), a classical tolerogen, was most effective; it produced antigen-specific tolerance, which was significantly enhanced by pre-treatment with TLI. Injection of HGG coupled to rat peritoneal cells induced a moderate degree of specific tolerance; in this case, pre-treatment with TLI added only nonspecific suppression. In contrast, AChR, either in solubilized form with no adjuvant, or coupled to syngeneic rat peritoneal cells, failed to induce tolerance, and actually primed the immune system, when given alone or in conjunction with TLI. Subsequent challenge with AChR resulted in an enhanced (secondary) anti-AChR antibody response. These results show that the nature of the antigen itself may predispose to tolerance or to immune stimulation. AChR appears to be highly immunogenic. However, if a tolerogenic fragment or form of AChR can be identified, its use in combination with TLI may result in specific tolerance. If such specific tolerance can be induced during an ongoing autoimmune reaction to AChR, it would be an effective treatment for myasthenia gravis.

Animals↗
PubMedDate not supplied

Haemoglobin E beta thalassaemia in Sri Lanka.

Haemoglobin E beta thalassaemia is the commonest form of severe thalassaemia in many Asian countries, but little is known about its natural history, the reasons for clinical diversity, or its management. We studied 109 Sri Lankan patients with the disorder over 5 years. 25 patients were not receiving transfusion; transfusion was stopped with no deleterious effect in a further 37. We identified several genetic and environmental factors that might contribute to the phenotypic diversity of the disorder, including modifiers of haemoglobin F production, malaria, and age-related changes in adaptive function. Our findings suggest that haemoglobin E beta thalassaemia can be managed without transfusion in many patients, even with low haemoglobin levels. Age-related changes in the pattern of adaptation to anaemia suggest that different and more cost-effective approaches to management should be explored.

Adolescent↗