INR: Intervals of measurement can safely extend to 14 weeks

The number of patients taking warfarin is increasing. Each of these patients requires regular blood tests to ensure that the level of anticoagulation reaches and remains within a defined target range. INR monitoring is expensive and time-consuming and the frequency of the tests has repercussions for NHS resources and patient convenience. Guidelines regarding this are available, but the research on which these are based is extremely limited. Many centres in the UK are using extended intervals between tests that exceed the current guidelines. This study shows that for selected patients the interval between INR tests can safely be extended to 14 weeks with the potential for longer intervals.

The incidence and cause of coagulopathies in an intensive care population

We studied 235 patients admitted to an adult intensive care unit in order to determine the incidence and cause of coagulation disturbances. Clinical coagulopathy, defined as bleeding unexplained by local or surgical factors, was identified in 13.6% of patients. Laboratory evidence of coagulopathy was more common: a prothrombin time (PT) ratio > or = 1.5 was found in 66% of patients and a platelet count <100 x 10(9)/l in 38% of patients. Both factors were predictive of excessive bleeding and poor outcome. In a retrospective analysis of plasmas from 45 of the above patients who had PT ratios > or = 1.5 the most common cause was vitamin K deficiency (20%).

Factors affecting results obtained with European Community tests for pasteurized milk sampled at the heat treatment establishment

A total of 3000 samples of pasteurized milk taken at the heat treatment establishment over a 1-year period were examined for the presence of phosphatase and by a plate count at 30 degrees C, a coliform count at 30 degrees C, and a plate count at 21 degrees C after pre-incubation of the sample for 5 days at 6 degrees C, performed as prescribed in EC Directive 85/397/EEC. Samples were also examined for presence of Listeria species. Of 2690 samples (1713 from small dairies and 977 from large commercial premises) received at 4 degrees C or less, 96 (3.6%) has a plate count at 30 degrees C exceeding 30,000 organisms per ml, 608 (22.6%) contained 1 or more coliforms per ml, and in 1327 (49.3%) the pre-incubated count exceeded 100,000 organisms per ml. Thirty two samples from 23 dairies contained phosphatase. Listeria species were detected in 25 samples; only three of these strains were identified as Listeria monocytogenes. Results were analysed to determine relationships between factors which might affect test results. Samples from small dairies showed significantly higher coliform counts and pre-incubated plate counts than did those from large commercial premises. They were also more likely to contain phosphatase or Listeria species. Samples were significantly more likely to contain coliforms when taken in the July-September quarter or if received in glass containers.

Response of T-beta CD8+ lymphocytosis-associated neutropenia to G-CSF

Only limited data are reported on the response to granulocyte-colony stimulating factor (G-CSF) of large granular lymphocytosis-associated neutropenia. We report features of such a case who developed a suppurating leg ulcer following a dog bite. G-CSF was used to increase the neutrophil count, allowing the ulcer to be successfully skin grafted.

A human macrophage-associated antigen (CD68) detected by six different monoclonal antibodies

Antibodies grouped together by the Third Workshop on Leucocyte Differentiation Antigens on the basis of pan-macrophage reactivity on tissue sections were analysed in immunoprecipitation experiments. Antibodies Y2/131, EBM11, Ki-M6 and Ki-M7 all precipitated antigens of Mr 110,000 which were shown to be identical by preclearing experiments. In addition a recently produced antibody, KP1, which identifies macrophages in paraffin-embedded tissue, was shown to recognize the same antigen. The antibodies were tested on murine cells transfected with two clones, which had been isolated by screening a cDNA library with antibodies Y1/82A and EBM11. Cells transfected with the longer cDNA clone, coding for a molecule of Mr 110,000, reacted with antibodies Y2/131, EBM11, Y1/82A and Ki-M6, whilst the shorter clone, encoding a molecule of Mr 70,000 gave the same result except that it did not induce expression of the Ki-M6 epitope. KP1 antibody did not recognize any transfectants, possibly because of differences in glycosylation by the transfected cell line compared with human tissue. Five of the six antibodies appear to recognize different epitopes (the sixth, Ki-M7, not having been evaluated in this way). It was concluded that these six antibodies react with a macrophage-associated antigen for which the gene has been cloned. This group of antibodies has recently been designated CD68 by the Fourth Workshop on Human Leucocyte Differentiation Antigens.

Serum amyloid A protein compared with C-reactive protein, alpha 1-antichymotrypsin and alpha 1-acid glycoprotein as a monitor of inflammatory bowel disease

The serum concentrations of serum amyloid A protein (SAA), C-reactive protein (CRP), alpha 1-antichymotrypsin (alpha 1-ACT) and alpha 1-acid glycoprotein (alpha 1-AGP) have been measured in eighty-six patients with Crohn's disease, twenty-five patients with ulcerative colitis and twenty-two patients with the irritable bowel syndrome. In the Crohn's and ulcerative colitis group significant increases in concentration were observed in all four proteins, which parallelled disease severity as defined by other conventional laboratory parameters formulated into a simple activity index. In the irritable bowel group no significant changes were seen. Serum amyloid A and CRP concentrations were significantly lower in ulcerative colitis than in Crohn's disease when mild, but did not differ significantly when severe. Serum amyloid A correlated well with CRP (r = 0.83) and alpha 1-ACT (r = 0.80), but less well with alpha 1-AGP (r = 0.65). Serum amyloid A was the most sensitive protein (77%) but had the lowest specificity (74%). C-reactive protein was less sensitive (58%) than SAA but had greater specificity (100%). Alpha 1-ACT had a sensitivity and specificity similar to CRP and, therefore, provided little or no additional information. Alpha 1-AGP, although also 100% specific, had the lowest sensitivity (34%) and, therefore, is probably the least useful acute phase monitor of inflammatory bowel disease. The role, and associated problems, of SAA measurements are discussed.