Michael G Lee

Endoscopic and gastric acid studies in homozygous sickle cell disease and upper abdominal pain.

Upper endoscopic and gastric acid output studies were done in 51 patients with homozygous sickle cell (SS) disease and recurrent epigastric pain. Twenty (39%) had abnormalities in the upper gastrointestinal tract including 18 (35%) with peptic ulcers. Mean basal and maximum acid output were similar in patients with and without duodenal ulcer (DU). Because DU in SS disease does not appear to be associated with high acid outputs observed in other populations, it may reflect reduced mucosal resistance, possibly resulting from ischaemia. This hypothesis was supported by the significantly lower fetal haemoglobin level among SS-DU patients.

Seroepidemiology of Helicobacter pylori infection in a Jamaican community.

Summary We researched epidemiologic associations between environmental and demographic factors and prevalence of Helicobacter pylori infection in a suburban Jamaican community. Using a clustered sampling technique, 22 domestic yards enclosing 60 separate households were randomly selected from a local community. All household members (n = 346) were invited to participate following informed consent; the overall compliance rate was 58.9%. A commercial enzyme immunoassay (HMáCAP) was used to detect IgG antibodies raised against H. pylori. Environmental and demographic information was obtained by questionnaire. The seroprevalence of H. pylori was 69.9% (n = 202). Analysis of the independent variables revealed three major components: Component 1 described, collectively, good personal hygiene and sanitation, indoor water supply and absence of straying animals in the peridomestic area; Component 2 included older age, good personal hygiene and large yard size; Component 3 the presence of domestic animals (cats and dogs) and, again, large yard size. These three complexes explained 42.2% of the variability in the data set. Logistic regression showed that Components 2 and 3 were independently associated with H. pylori seropositivity, indicating that a combination of demographic, environmental and zoonotic factors is involved in the spread of H. pylori infections at the tropical community level.

Characteristics of Helicobacter pylori infection in Jamaican adults with gastrointestinal symptoms.

ABSTRACT Helicobacter pylori infection is common in Jamaica. Describing its epidemiology in a population-based study depends largely on serology, but serologic assays have not been validated in this population. To address this issue, we examined the presence ofH. pylori infection in 30 sequential adult patients with gastroduodenal symptoms by three biopsy-based methods (rapid urease test, histology, and culture) as well as by one research and two commercial enzyme-linked immunosorbent assays (ELISAs). A patient was considered H. pylori positive if the organism was detected by at least one biopsy-based method. Eighteen (60%) of the 30 patients were H. pylori positive by these criteria, whereas 21 (70%) were seropositive for H. pyloriimmunoglobulin G by our research ELISA. The presence of H. pylori infection in patients with gastric cancer and those with chronic gastritis was missed by biopsy-based methods but was detected by serologic assays. This observation indicates that serologic assays may be better suited for the detection of this infection in a population in which H. pylori-associated pathology is prevalent. The performance of our research ELISA in detecting biopsy-based H. pylori-positive cases was excellent, with a sensitivity and specificity of 100% and 75%, respectively. Molecular genotyping of the isolates revealed that the predominant H. pylori genotypes in this cohort of Jamaicans were cagA+ vacA slb-m1, andiceA2. The validated serologic assay enables us to interpret epidemiologic data from population-based studies in Jamaica by comparison to those from other populations.

Drug-induced acute liver disease.

Fifty-three patients with drug-induced acute liver disease are reported. There were 35 females and 18 males with a mean age of 41 years. All but one patient had jaundice or hyperbilirubinaemia and 51 had abnormal liver enzymes. Histologically 38 patients (72%) had cholestatic injury while 15 had cytotoxic parenchymal damage. Methyldopa, chlorpropamide, chlorpromazine, halothane and the contraceptive pill accounted for 60% of cases. Fifty-one patients recovered after drug withdrawal while 2 died of hepatic failure. Drug-induced liver injury must be considered in patients presenting with evidence of hepatic disease as the majority will recover on withdrawal.

A Review of Pharmacovigilance.

Pharmacovigilance supports safe and appropriate use of drugs. Spontaneous reporting of adverse drug reactions (ADRs) is an essential component of pharmacovigilance. However, there is significant underreporting of ADRs. Adverse drug reactions have become a major problem in developing countries. Knowledge of pharmacovigilance could form the basis for interventions aimed at improving reporting rates and decreasing ADRs.

Colon cancer screening

FOBT – Patients whose positive FOBT is caused by neoplasms often have advanced colon cancer (i.e., larger cancers cause more blood loss and more likely to be caught at any given point in time). Flexible sigmoidoscopy – Patients only have about 30-40% of their total colon examined during this procedure. They are not sedated, and the prep consists of only 2 enemas on the morning of their exam ± magnesium citrate the night before. If the colon cancer is not within the descending colon, rectum, or sigmoid area then it will be missed on this exam. Flexible sigmoidoscopy screening has been shown to reduce the mortality of colorectal cancer by about 25%. Double contrast BE with Flex Sig – The BE will look at the ascending colon and transverse colon, which cannot be seen with the flexible sigmoidoscopy. If there are any lesions noted on BE, then the GI service will have to perform a colonoscopy to ascertain the pathology of the lesion. Colonoscopy – This gives direct visualization of the total colon and is the gold standard to which other screening methods are compared. It has the added advantage of allowing biopsy or removal of any lesions seen during the procedure, in particular adenomatous polyps which are thought to be precancerous lesions. For this procedure the patient’s entire colon must be prepped, which will involve the entire day prior to the procedure. Because conscious sedation is employed, the patient must have a ride home after the procedure.

Clinical Factors Associated with Morbidity and Mortality in Patients Admitted with Sickle Cell Disease.

OBJECTIVE To determine the clinical factors associated with the length of hospitalization and mortality in patients with sickle cell disease (SCD). METHODS All patients with SCD admitted to the medical wards of the University Hospital of the West Indies, Jamaica, over a five-year period, January 1 to December 31, 2010, were reviewed. Data were extracted from hospital charts and comprised demographic and clinical information, investigations, interventions, duration of stay, pathological data and outcomes. RESULTS There were 105 patients reviewed; 84% were genotype Hb SS. Females accounted for 59% and males 41%. Overall mean age was 32.5 years (SD 13.7, range 12-66 years). The mean length of hospitalization was 10.2 days (SD 10.9, range 1-84 days). The main admission diagnoses were painful crisis, acute chest syndrome, severe anaemia, sepsis, hepatic sequestration, congestive cardiac failure and renal failure. The mean value for the following laboratory investigations were: haemoglobin 7.7 g/dL (SD 2.8), total white blood cell count 21.7 x 109/L (SD 14.2), platelet count 320 x 109/L (SD 191.9), blood urea 9.8 mmol/L (SD 11.9) and serum creatinine 198 umol/L (SD 267.9). Medical interventions included: blood transfusions in 20.9%, 55% received antibiotics and 74% received narcotic analgesia. There were 40 deaths with four autopsies done. The mortality rate for SCD was 38%. There were 189 repeat SCD admissions. CONCLUSION Sickle cell disease still carries a high morbidity and mortality in patients admitted to hospital. Recurrent admissions are a concern, as they impact on patients morbidity and quality of life.

Gentamicin Therapeutic Drug Monitoring: Importance in the Hospital Setting

Background: The use of gentamicin places patients at risk of developing drug-induced nephrotoxicity, requiring special consideration to be given to serum creatinine monitoring and therapeutic drug monitoring (TDM). Objectives: To evaluate the prevalence of nephrotoxicity without the availability of TDM. Methods: A prospective study was used to recruit patients, 18 years and older who were to receive intravenous gentamicin administration between July 2013 and July 2014 at the University Hospital of the West Indies. Their data collected included: demographics, type of infection, gentamicin dose regimen, concomitant drugs and serum creatinine. Nephrotoxicity was defined as 1.5 times or more increase in serum creatinine concentration above the baseline. Results: Eleven patients were included in the study; six (55%) were males, their median age was 51 years (range: 33–84 years). All the patients had normal baseline serum creatinine, median 56 (range: 22–94) μmol/L and had regular monitoring of serum creatinine during therapy. The median gentamicin dose was 160 mg/day (range: 50–240 mg/day) and median treatment length was eight days (range: 5–30 days). Evidence of nephrotoxicity was observed in six (55%) patients by day seven of therapy. All the patients had at least one risk factor predisposing them to nephrotoxicity including prolonged therapy (10/11), multiple daily dosing regimen (8/11), receiving concomitant nephrotoxic drugs (9/11) and age (6/11). Conclusion: Although vigilant monitoring of serum creatinine is useful for safety monitoring, with most patients experiencing some levels of nephrotoxicity and having at least one predisposing risk factor, consideration should be given to the implementation of TDM.

A Review of Clostridium difficile Infection at the University Hospital of the West Indies, Jamaica

OBJECTIVES This study examined the frequency of Clostridium difficile infection (CDI) among hospital admission and diarrhoeal stool samples over a six-year period. METHODS A review of all suspected cases of C difficile positive patients from 2007 to 2012 at the University Hospital of the West Indies (UHWI), Jamaica, was performed. Clostridium difficile infection was confirmed by clinical features and a positive enzyme-linked immunosorbent assay (ELISA) stool test for Clostridium Toxins A and B. The demographics, clinical features, risk factors, treatment and outcomes were also examined. RESULTS There were 56 patients reviewed. The most commonly affected age group was 40-59 years of age. The proportion of CDI cases per total stool samples increased from 0.5% in 2007 to 5.9% in 2010 then fell to 2.2% in 2011 but increased again to 4.3% in 2012. The proportion of cases per total UHWI admissions also increased from 0.12 cases per 1000 admissions in 2007 to 1.16 in 2010 and 1.36 in 2012 (p < 0.001). Most CDI cases were nosocomial (76% males, 48.6% females). Co-morbidities included hypertension and end-stage renal disease. Ceftazidime was the most common antibiotic associated with the development of CDI. Resolution occurred in 62.5% of patients. Duration of hospital stay was longer in males than females (≥ 21 versus < 7 days) and males had more adverse outcomes, with death in 23.8% versus 11.4%. CONCLUSION There has been an increase in the frequency of CDI at UHWI with a greater than expected frequency of community acquired CDI. Increased awareness is needed of the increasing risk for CDI and measures must be taken to prevent the disease, especially in hospitalized patients.

Whipple's disease in an Afro-Caribbean national

Whipples disease is a rare multi-organ infectious disease caused by Tropheryma whipplei. It is fatal without treatment. We report on a 40-year old Afro-Jamaican man who presented with a six-month history of weight loss and diarrhoea. Investigations revealed iron deficiency anaemia and hypoalbuminaemia. Upper gastrointestinal endoscopy revealed white patchy lesions in the duodenum. The duodenal biopsy showed broadening and thickening of the villi by a dense infiltrate of foamy histiocytes within the lamina propria and focally extending into the attached submucosa. Periodic Acid-Schiff stains were positive. Electron microscopy was confirmatory and polymerase chain reaction testing conclusively identified the organisms as T whipplei. Antibiotic treatment resulted in resolution of symptoms. Although the diagnosis of Whipples disease is difficult, increased awareness should lead to an increase in reported cases with the improvements in diagnostic capabilities.