Variations in the evaluation of colorectal cancer risk

OBJECTIVES: To test the variability in estimating cancer risk and demonstrate the consequences that subjectivity has on patient care. SUBJECTS AND METHODS: Forty-three clinicians were each asked to assess 40 symptomatic colorectal referrals. Each clinician was provided with a comprehensive history on the 40 patients. The clinicians graded the referral according to a malignancy risk score, decided on the required first line investigation and the priority of that investigation. The main outcome measures used was accuracy in cancer detection and appropriateness of investigations selected. RESULTS: There was a wide degree of variation among all clinicians grading both benign and malignant disease with the overall correct classification of 54% (P-value of <0.001). On average, the clinicians correctly diagnosed 71.3% of the cancer patients as compared to 44% of the benign patients. Of the cancer patients, 47% were correctly classified as an urgent referral whilst 52% of the benign patients were over classified and graded as an urgent referral. The mean number chosen by clinicians to have a flexible sigmoidoscopy as the appropriate first investigation was 13 (of 40 patients); this was despite the diagnosis being possible in all cases with a flexible sigmoidoscopy. The choice to use full colonic investigation was seen throughout all disciplines. Junior doctors demonstrated the highest tendency choosing full colonic investigation in 92.3%. Consultants and senior grades showed the least tendency to choose full colonic imaging although even here colonoscopy or barium enema represented 48.5%. CONCLUSION: Subjective assessment of cancer referrals is a significant problem that needs to be confronted. Improvements are needed to resolve the inherent problems of subjectivity and operator bias if uniform quality of patient care and best use of resources is to be achieved.     

Quantitation and characterization of glutathionyl haemoglobin as an oxidative stress marker in chronic renal failure by mass spectrometry

OBJECTIVES: Glutathionyl haemoglobin (GS-Hb) belonging to the class of glutathionylated proteins has been investigated as a possible marker of oxidative stress in different chronic diseases. The purpose of this study was to examine whether glutathionyl haemoglobin can serve as an oxidative stress marker in non-diabetic chronic renal failure patients on different renal replacement therapies (RRT) through its quantitation, and characterization of the specific binding site of glutathione in haemoglobin molecule by mass spectrometric analysis. DESIGN AND METHODS: The study group consisted of non-diabetic chronic renal failure patients on renal replacement therapy (RRT): hemodialysis (HD), continuous ambulatory peritoneal dialysis (CAPD) and renal allograft transplant (Txp) patients. Haemoglobin samples of these subjects were analyzed by liquid chromatography electrospray ionization mass spectrometry for GS-Hb quantitation. Characterization of GS-Hb was done by tandem mass spectrometry. Levels of erythrocyte glutathione (GSH) and lipid peroxidation (as thiobarbituric acid reacting substances) were measured spectrophotometrically, while glycated haemoglobin (HbA1c) was measured by HPLC. RESULTS: GS-Hb levels were markedly elevated in the dialysis group and marginally in the transplant group as compared to the controls. GS-Hb levels correlated positively with lipid peroxidation and negatively with the erythrocyte glutathione levels in RRT groups indicating enhanced oxidative stress. De novo sequencing of the chymotryptic fragment of GS-Hb established that glutathione is attached to Cys-93 of the beta globin chain. Mass spectrometric quantitation of total glycated haemoglobin showed good agreement with HbA1c estimation by conventional HPLC method. CONCLUSIONS: Glutathionyl haemoglobin can serve as a clinical marker of oxidative stress in chronic debilitating therapies like RRT. Mass spectrometry provides a reliable analytical tool for quantitation and residue level characterization of different post-translational modifications of haemoglobin.     

Occupational health in Saudi Arabia

The Kingdom of Saudi Arabia is rapidly industrializing, and the economy is now less dependent on oil. The future of industrial growth is very bright. Two industrial complexes (at the Arabian Gulf and the Red Sea coasts) of eight provide the basis for the Kingdom s programs to develop hydrocarbon-based and energy-intensive industries. Expatriates form the driving workforce in industry. Today, more Saudis are being recruited and trained to man the factories. Occupation-related disorders in industry vary from minor irritations to injuries and cancers. However, the risk of massive releases of toxic chemicals is not great. The national Occupational Health Service directorate is based at the Ministry of Health. Together with the Ministry of Labor, it assumes the overall supervision of industrial health and safety. However, there are constraints the most important of which is the lack of enough qualified Saudis in this field.     

Pulmonary effects of occupational exposure to Portland cement: a study from eastern Saudi Arabia

A cross-sectional study was conducted in a randomly selected factory producing Portland cement in eastern Saudi Arabia to determine the prevalence of respiratory symptoms and diseases and chest x-ray changes consistent with pneumoconiosis in the employees. A sample of 150 exposed and 355 unexposed employees was selected. A questionnaire about respiratory symptoms was completed during an interview. Chest x-rays were read according to the ILO criteria for pneumoconiosis. Dust level was determined by the gravimetric method. Concentrations of personal respirable dust ranged from 2.13 mg/m3 in the kilns to 59.52 mg/m3 in the quarry area. Cough and phlegm were found to be related to cigarette smoking, while wheezing, shortness of breath, and bronchial asthma were related to dust levels. It is recommended that engineering measures be adopted to reduce the dust level in this company, together with health monitoring of exposed employees.     

Rotavirus and enteric pathogens in infantile diarrhoea in Manipal,South India

The etiology of Rotavirus in acute diarrhoeal illness in children 0–5 years of age, admitted to the pediatric wards of Kasturba Medical College Hospital, Manipal was studied over a period of 5 years. Rotavirus in the faeces detected by Latex agglutination test accounted for 19.56% of the diarrhoea with maximum incidence (65%) in the 7–12 months of age group. Bacterial aetiological agents continued to play a significant role (69.6%) in diarrhoeal diseases.Enteroaggregative E. coli was common in the age group between 25–36 months, Shigellosis in 37–60 months andSalmonella typhimurium enteritis in 7–12 months of age. The other pathogens isolated werevibrio cholerae (4.98%), species of aeromonas (15.92%), along with cryptosporidium (6.47%) and Candida albicans (3.98%). In a control group consisting of 100 children without history of diarrhoea, 2 were positive for rotavirus, 3 for cryptosporidium and 12 forEscherichia coli.     

Cryptosporidium and isospora belli diarrhoea in immunocompromised hosts

Cryptosporidium and isospora, two of the intestinal coccidian parasites known to be the causative agents of acute diarrhoea in animals, have now emerged as one of the main causes of prolonged life threatening diarrhoea in immunocompromised patients particularly so in patients with AIDS. Between June 1996 and December 1997, a total of 75 immunocompromised patients presenting with diarrhoea were investigated both for Cryptosporidium and Isospora. The study group consisted of cancer and AIDS patients with history of diarrhoea. Cryptosporidium oocysts were detected in 35 patients (46.7%). One of the faecal samples from an AIDS patient with diarrhoea showed the presence of both Cryptosporidium and Isospora oocysts. To the best of our knowledge, this is the second documented report of Isospora associated diarrhoea in an AIDS patient from India. The various techniques used for demonstration of these parasites were modified acid fast staining, Safranine Methylene-blue staining and direct immunofluorescence test.