M M Fonseka

University of Kelaniya, Kelanai, Western, Sri Lanka

Are you M M Fonseka?

Claim your profile

Publications (21)68.78 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The outcome of snakebite is related to the biting species but it is often difficult to identify the biting snake, particularly in community settings. We have developed a clinical scoring system suitable for use in epidemiological surveys, with the main aim of identifying the presumed biting species in those with systemic envenoming who require treatment. The score took into account ten features relating to bites of the five medically important snakes in Sri Lanka, and an algorithm was developed applying different weightings for each feature for different species. A systematically developed artificial data set was used to fine tune the score and to develop criteria for definitive identification. The score was prospectively validated using 134 species-confirmed snakebites. It correctly differentiated the bites caused by the three snakes that commonly cause major clinical problems (Russell's viper (RV), kraits and cobra) from other snakes (hump-nosed viper (HNV) and saw-scaled viper (SSV)) with 80% sensitivity and 100% specificity. For individual species, sensitivity and specificity were, respectively: cobra 76%, 99%; kraits 85%, 99%; and RV 70%, 99%. As anticipated, the score was insensitive in the identification of bites due to HNV and SSV.
    Transactions of the Royal Society of Tropical Medicine and Hygiene 10/2006; 100(9):874-8. · 1.82 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Snake bite is a common cause of hospital admission in Sri Lanka. Despite this, there have been no countrywide studies or national estimates of disease burden due to snake bites in Sri Lankan hospitals. We assessed the disease burden due to snake bite in our hospitals and estimated the frequency of admissions due to bites by different snake species. Sri Lanka was divided into four zones based on climate and topography. Hospital morbidity and mortality data, which are available on an administrative district basis, were collated for the four zones. A survey of opinion among specialist physicians (the Delphi technique) was used to estimate the proportion of bites by different species, and requirements for anti-venom (AV) and intensive care facilities for management of snake bites in hospitals in each of the four zones. A study of hospital admissions due to snake bites in seven selected hospitals was also performed to validate the opinion survey. There was a clear difference in the incidence of hospital admissions due to snake bites in the different zones. Estimates of hospital admissions due to bites by different species also varied considerably between zones. These trends corresponded to estimates of requirements of AV and other supportive health care. Health care planning using data based on environmental information, rather than merely on political boundaries, could lead to targeted distribution of AV and intensive care requirements to manage snake bites.
    The Southeast Asian journal of tropical medicine and public health 06/2005; 36(3):733-40. · 0.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Deliberate self-poisoning with yellow oleander seeds is common in Sri Lanka and is associated with severe cardiac toxicity and a mortality rate of about 10%. Specialised treatment with antidigoxin Fab fragments and temporary cardiac pacing is expensive and not widely available. Multiple-dose activated charcoal binds cardiac glycosides in the gut lumen and promotes their elimination. We aimed to assess the efficacy of multiple-dose activated charcoal in the treatment of patients with yellow-oleander poisoning. On admission, participants received one dose of activated charcoal and were then randomly assigned either 50 g of activated charcoal every 6 h for 3 days or sterile water as placebo. A standard treatment protocol was used in all patients. We monitored cardiac rhythm and did 12-lead electocardiographs as needed. Death was the primary endpoint, and secondary endpoints were life-threatening cardiac arrhythmias, dose of atropine used, need for cardiac pacing, admission to intensive care, and number of days in hospital. Analysis was by intention to treat. 201 patients received multiple-dose activated charcoal and 200 placebo. There were fewer deaths in the treatment group (five [2.5%] vs 16 [8%]; percentage difference 5.5%; 95% CI 0.6-10.3; p=0.025), and we noted difference in favour of the treatment group for all secondary endpoints, apart from number of days in hospital. The drug was safe and well tolerated. Multiple-dose activated charcoal is effective in reducing deaths and life-threatening cardiac arrhythmias after yellow oleander poisoning and should be considered in all patients. Use of activated charcoal could reduce the cost of treatment.
    The Lancet 07/2003; 361(9373):1935-8. · 39.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Deliberate self-harm by ingestion of organophosphate insecticides is a common health problem in Sri Lanka. The poisoning results in an initial life-threatening cholinergic crisis and several intermediate and late neurological and psychiatric manifestations. A patient who developed self-limiting cerebellar signs 8 days after ingestion of dimethoate, an organophosphorous insecticide, is reported on.
    Human &amp Experimental Toxicology 03/2003; 22(2):107-9. · 1.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Liv.52, a hepatoprotective agent of herbal origin, is used empirically for the treatment of alcoholic liver disease in Sri Lanka. We conducted a controlled trial to assess the efficacy of Liv.52 in patients with alcoholic liver disease. Patients with evidence of alcoholic liver disease attending outpatient clinics were included in a prospective, double blind, randomized, placebo controlled trial. During the trial period, 80 patients who fulfilled inclusion criteria were randomly assigned Liv.52 (cases; n = 40) or placebo (controls) the recommended dose of three capsules twice daily for 6 months. All patients underwent clinical examination (for which a clinical score was computed), and laboratory investigations for routine blood chemistry and liver function before commencement of therapy (baseline). Thereafter, clinical assessments were done monthly for 6 months, while laboratory investigations were done after 1 and 6 months of therapy. There was no significant difference in the age composition, alcohol intake and baseline liver function between the two groups. The two-sample t-test was used to analyze data obtained after 1 and 6 months of therapy against baseline values. There was no significant difference in clinical outcome and liver chemistry between the two groups at any time point. There were no reports of adverse effects attributable to the drug. Our results suggest that Liv.52 may not be useful in the management of patients with alcohol induced liver disease.
    Journal of Ethnopharmacology 02/2003; 84(1):47-50. · 2.94 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cardiac toxicity after self-poisoning from ingestion of yellow oleander seeds is common in Sri Lanka. We studied all patients with yellow oleander poisoning (YOP) admitted to a secondary care hospital in north central Sri Lanka from May to August 1999, with the objective of determining the outcome of management using currently available treatment. Patients with bradyarrhythmias were treated with intravenous boluses of atropine and intravenous infusions of isoprenaline. Temporary cardiac pacing was done for those not responding to drug therapy. During the study period 168 patients with YOP were admitted to the hospital (male:female = 55:113). There were six deaths (2.4%), four had third-degree heart block and two died of undetermined causes. They died soon after delayed admission to the hospital before any definitive treatment could be instituted. Of the remaining 162 patients, 90 (55.6%) patients required treatment, and 80 were treated with only atropine and/or isoprenaline while 10 required cardiac pacing in addition. Twenty-five (14.8%) patients had arrhythmias that were considered life threatening (second-degree heart block type II, third-degree heart block and nodal bradycardia). All patients who were treated made a complete recovery. Only a small proportion of patients (17%) admitted with YOP developed life-threatening cardiac arrhythmias. Treatment with atropine and isoprenaline was safe and adequate in most cases.
    Human &amp Experimental Toxicology 07/2002; 21(6):293-5. · 1.45 Impact Factor
  • Source
    Ceylon Medical Journal 07/2002; 47(2):43-5.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To study the safety of low dose subcutaneous adrenaline given as prophylaxis against acute adverse reactions to anti-venom serum (AVS) in patients bitten by snakes. Patients admitted with snakebite envenoming who satisfied inclusion criteria were given 0.25 ml of 1:1000 adrenaline subcutaneously immediately before administration of AVS. They were observed for adverse effects, and pulse and blood pressure (BP) were monitored. 51 patients [35 males, mean age 34.8 years (SD 14)] were included in the study. Adverse reactions to AVS occurred in 15 (29.4%) patients. There was one death from suspected cerebral haemorrhage, and 3 (5.9%) patients developed small haematomas at the subcutaneous injection site. There were no significant changes in mean pulse or BP following administration of subcutaneous adrenaline. Low dose subcutaneous adrenaline did not cause significant changes in pulse rate or BP. Although the death was unlikely to be directly related to subcutaneous adrenaline, we suggest further studies on the safety of this prophylactic treatment before its routine use.
    Ceylon Medical Journal 07/2002; 47(2):48-9.
  • Transactions of the Royal Society of Tropical Medicine and Hygiene 01/2002; 96(3):272-4. · 1.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Parasuicide by ingestion of organophosphate (OP) insecticides is common in Sri Lanka, but the use of the parateral route to self administer the poison is extremely rare. We report a patient who deliberately injected herself intramuscularly with an OP compound with suicidal intent. The clinical manifestations of OP poisoning were unpredictable and posed a therapeutic problem.
    Human &amp Experimental Toxicology 08/2001; 20(7):377-8. · 1.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We describe severe hepatic dysfunction associated with an attack of falciparum malaria in six Sri Lankan patients. Clinicians working in areas endemic for malaria should be made aware of this unusual complication.
    The Southeast Asian journal of tropical medicine and public health 04/2001; 32(1):70-2. · 0.61 Impact Factor
  • Ceylon Medical Journal 01/2000; 44(4):190-1.
  • Ceylon Medical Journal 01/2000; 44(4):188-9.
  • Ceylon Medical Journal 10/1999; 44(3):130-2.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cardiac effects following the bite of Burmese Russell's vipers and European vipers are well known. The question whether envenomation caused by Sri Lankan viper bites results in myocardial damage remains largely unanswered. The aim of this prospective study was to investigate whether myocardial damage occurs after Sri Lankan viper bites, using a highly specific and sensitive marker, troponin T. 45 patients admitted after a definite viper bite [Russell's viper (RV), n = 13, hump-nosed viper (HNV), n = 32] were studied with regard to cardiac symptoms, ECG changes, and troponin T levels. There were no admissions with bites of other types of Sri Lankan vipers during the study period. Cardiac symptoms were present in a number of patients following the bite. Two patients had transient ECG changes. However, troponin T levels were not elevated in any of them. Myocardial damage does not seem to be an important feature of Sri Lankan Russell's and hump-nosed viper bites. This may be because of venom heterogeneity in vipers, that is based on their geographical distribution.
    Ceylon Medical Journal 07/1999; 44(2):70-3.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To assess the efficacy and safety of low dose adrenaline injected subcutaneously to prevent acute adverse reactions to polyspecific antivenom serum in patients admitted to hospital after snake bite. Prospective, double blind, randomised, placebo controlled trial. District general hospital in Sri Lanka. 105 patients with signs of envenomation after snake bite, randomised to receive either adrenaline (cases) or placebo (controls) immediately before infusion of antivenom serum. Adrenaline 0.25 ml (1:1000). Development of acute adverse reactions to serum and side effects attributable to adrenaline. 56 patients (cases) received adrenaline and 49 (controls) received placebo as pretreatment. Six (11%) adrenaline patients and 21 (43%) control patients developed acute adverse reactions to antivenom serum (P=0.0002). Significant reductions in acute adverse reactions to serum were also seen in the adrenaline patients for each category of mild, moderate, and severe reactions. There were no significant adverse effects attributable to adrenaline. Use of 0.25 ml of 1:1000 adrenaline given subcutaneously immediately before administration of antivenom serum to patients with envenomation after snake bite reduces the incidence of acute adverse reactions to serum.
    BMJ Clinical Research 05/1999; 318(7190):1041-3. · 14.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate whether people who have committed parasuicide have low serum cholesterol concentrations. All subjects admitted to the University Medical Unit, Ragama after parasuicide from 1.3.96 to 31.1.97 were matched for age, sex, presence of diabetes and arterial hypertension, substance abuse, body mass index and socioeconomic status with controls. Venous blood samples for cholesterol estimation were collected from parasuicides within 24 hours of admission. Analysis was done on 168 parasuicide patients [males 74; mean age for males 24 years (SD 6.2), females 19 years (SD 3.3)] and 168 matched controls. Of the parasuicide subjects, 33 had a psychiatric illness and 135 were considered to have impulsive personalities. The serum cholesterol level in parasuicide patients was not significantly different from that in controls. This study, the first from a developing country, did not show an association between low serum cholesterol concentrations and parasuicide.
    Ceylon Medical Journal 04/1999; 44(1):11-3.
  • [Show abstract] [Hide abstract]
    ABSTRACT: As electrical stimulation of the rectum has been shown to result in reflex internal sphincter inhibition mediated by intrinsic nerves, we aimed to evaluate the integrity of these nerves in the rectum of diabetic patients. Anal canal pressure, recto-anal inhibitory reflex (RAIR) and continence were evaluated in 30 diabetic patients (male:female 13:17, median age 57 years, range 37-70) and these data were compared with similar data obtained from 22 age- and sex-matched healthy controls (male:female 9:13, median age 51 years, range 19-65 years). Median duration of diabetes was 8 years (range 3-30). Twelve (40%) of the 30 diabetics had impaired continence for gas (n = 12) and liquid faeces (n = 3). None of the controls had incontinence. Median maximum resting anal canal pressure (MRP) was: patients 30 mmHg (range 20-75 mmHg) versus controls 40 mmHg (range 20-105 mmHg, P = 0.61). Median maximum squeeze pressure (MSP) was 65 mmHg (range 30-150 mmHg) in patients versus 84mmHg (range 35-230 mm Hg) in controls (P = 0.59). Median threshold rectal mucosal electrosensation (RMES-T) was 27mA (5-40 mA) in patients versus 13 mA (5-28 mA) in controls (P = 0.03). Maximum tolerable rectal mucosal electrosensation was 40 mA (20-60) in patients versus 20 mA (10-30), in controls (P = 0.042, all comparisons using the Wilcoxon rank test). Recto-anal inhibitory reflex was present in eight, abnormal in five (one incontinent) and absent in 17 (11 incontinent) diabetics, while it was present in 18 and abnormal in four controls (test of proportion, P = 0.031). Blood glucose in diabetics on the day of the procedure was 98 mg/dL (70-165 mg/dL). Rectal mucosal electrosensitivity and RAIR were impaired in significantly more patients with diabetes than controls, implying impairment of intrinsic neuronal function. The recto-anal inhibitory reflex was either impaired or absent in all diabetic patients with incontinence.
    Journal of Gastroenterology and Hepatology 12/1998; 13(11):1107-10. · 3.33 Impact Factor
  • Ceylon Medical Journal 04/1998; 43(1):33.
  • Ceylon Medical Journal 01/1998; 42(4):183-4.