PubMed Health⌕ Search

Biomedical subjects

I N Ross

Publications and source records attributed to I N Ross.

11 recordsLinked to original sources
PubMed1987

Predicting enteric fever without bacteriological culture results.

We used Bayes' theorem to calculate the probability of enteric fever in 260 patients presenting with undiagnosed fever, without recourse to blood or stool culture results. These individuals were divided into 110 patients with enteric fever (63 culture positive, 47 culture negative) and 150 patients with other causes of fever. Comparison of the frequencies of occurrence of 19 clinical and laboratory events, said to be helpful in the diagnosis of enteric fever, in the two groups revealed that only 8 events were significantly more frequent in enteric fever. These were: a positive Widal test at a screening dilution of 1:40; a peak temperature greater than = 39 degrees C; previous treatment for the fever; a white blood cell count less than 9 X 10(6)/litre; a polymorphonuclear leucocyte count less than 3.5 X 10(6)/litre; splenomegaly; fever duration greater than 7 d; and hepatomegaly. When the probability of enteric fever was determined prospectively in 110 patients, using only 6 of these discriminating events, the probability of patients with a positive prediction having enteric fever (diagnostic specificity) was 0.80 (95% confidence interval: 0.68 to 0.91) and the probability of those with a negative prediction not having enteric fever (diagnostic sensitivity) was 0.92 (0.85 to 0.99). Using all 19 events did not alter the diagnostic specificity or diagnostic sensitivity. This study shows that a small number of clinical and laboratory features can objectively discriminate enteric fever from other causes of fever in the majority of patients. Calculating the probability of enteric fever can aid in diagnosis, when culturing for salmonella is either unavailable or is negative.

Bayes Theorem↗
PubMed1987

Reassessment of faecal alpha-1-antitrypsin excretion for use as screening test for intestinal protein loss.

Faecal alpha-1-antitrypsin and 51Cr-albumin losses in 42 patients with either gastrointestinal or hepatic disease were compared. The reference range was derived from measurements in 20 controls without gastrointestinal disease. Alpha-1-antitrypsin excretion was increased in patients with excessive 51Cr-albumin loss, and correlations were found between alpha-1-antitrypsin clearance and 51Cr-albumin excretion. Because of the considerable overlap of faecal alpha-1-antitrypsin excretion between controls and patients, sensitivity and specificity of the test were only 58% and 80%, respectively. This poor reliability could not be explained by sampling error or temporal variations in alpha-1-antitrypsin excretion. These results show that although faecal alpha-1-antitrypsin excretion correlates with 51Cr-albumin excretion when whole groups of patients are studied, its poor sensitivity makes it an unreliable measure of enteric protein loss.

Albumins↗
PubMed1986

Diagnosing enteric fever: a reappraisal.

The diagnostic value of 19 clinical and laboratory events was assessed in 150 enteric fever cases. A logistic regression analysis revealed only 8 predicitive variables for the presence or absence of enteric fever. These were, in order of importance, the white blood cell count, the S. typhi H agglutinin titre, body temperature, the S. typhi O agglutinin titre, the S. paratyphi A H agglutinin titre, the S. paratyphi B H agglutinin titre, age and the fever pattern. This study showed that objective variables like the Widal titres were useful in predicting enteric fever, whilst symptoms such as abdominal pain were unhelpful. Use of all 8 variables to calculate the probability of enteric fever might provide an accurate method of diagnosing or confirming enteric fever when culture results are unavailable or negative.

Adult↗
PubMed1979

Significance of serum complement levels in patients with gastrointestinal disease.

Levels of the serum complement components, C3 and C4, in patients with Crohn's disease, ulcerative colitis, and miscellaneous gastrointestinal disorders were compared with those of normal blood donors. Significant increases of both components were found in all three patient groups, the highest being in patients with Crohn's disease. Generally, levels of C3 and C4 were lower in patients with inactive rather than active Crohn's disease and ulcerative colitis. These results provide some evidence in support of an immunological basis for inflammatory bowel disease. However, in view of the frequent elevation of C3 and C4 in other gastrointestinal diseases, it is equally possible that the complement components are behaving as acute phase proteins.

Blood Donors↗
PubMed1978

Whipple's disease in a female with impaired cell-mediated immunity unresponsive to co-trimoxazole and levamisole therapy.

A case of Whipple's disease in a female is described. Malabsorption of iron, vitamin B12, folic acid and fat was present. These abnormalities reverted to normal after introduction of co-trimoxazole therapy. The patient's humoral immune system was normal, in contrast to impairment of cell-mediated immunity, which has not improved in spite of co-trimoxazole treatment for 2 years, and a therapeutic trial of levamisole. These findings are further evidence that there may be a primary immune deficiency in patients with Whipple's disease.

Drug Combinations↗
PubMed1978

The ageing gut: a study of intestinal absorption in relation to nutrition in the elderly.

This study was designed to assess the functional efficiency of the ageing small intestine and the possible role of malabsorption in old people with nutritional deficiencies. Fifty subjects aged 65 to 92 years were studied, of whom 33 presented with anaemia, chronic diarrhoea or bone pains, and 17 were apparently healthy 'controls' with no relevant symptoms. Tests of intestinal function included blood xylose and iron absorption curves, a double isotope Schilling test, faecal fat, urinary indican and small bowel radiology, with duodenal aspiration and jejunal biopsy in some cases. On the basis either of steatorrhoea or at least two other abnormal parameters of absorption, there were 15 cases of malabsorption. Thirteen of these had symptoms but two were 'controls'. Four of these had duodenal diverticulosis, two had the post-gastrectomy syndrome, and one had calcific pancreatitis. Malabsorption in the remaining eight cases was not fully explained. The age range of this last group was 72--86 years; one of them had a contaminated small bowel and two showed some evidence of pancreatic insufficiency. Malabsorption emerged as a significant cause of low levels of serum iron, haemoglobin and calcium. The blood xylose test is a useful screening procedure for intestinal malabsorption in old age, but full evaluation calls for investigation of pancreatic function.

Aged↗
PubMed1977

IgG myeloma presenting as ulcerative colitis.

Two patients who presented with ulcerative colitis are described. Both were found to have evidence of IgG monoclonal gammopathy and Bence-Jones proteinuria. This association has been reported previously only in the presence of myelomatous infiltration of the gastrointestinal tract or in amyloidosis, and hence the cases reported appear to be unique.

Bence Jones Protein↗
PubMed1976

Severe selective IgM deficiency.

Among the primary antibody deficiency syndromes, severe selective IgM deficiency (also previously known as type V dysgammaglobulinaemia) is rare, and the majority of previous reports have indicated a fatal outcome. Three adult patients who were found to have a persistently low serum IgM are described. This deficiency was not obviously related to their presenting illness; in two of the patients, who were investigated in detail, it appeared to be of no immediate consequence.

Aged↗