Assessment of the diagnoses of Crohn's disease and ulcerative colitis in a Danish hospital information system.

BACKGROUND: Our aim was to estimate the completeness-that is, whether all patients were included in the system-and the validity-that is, whether the diagnostic criteria were fulfilled for the patients registered-of the diagnoses of Crohn's disease and ulcerative colitis in a Danish hospital system. METHODS: Information in a regional hospital system, in the County of North Jutland, Denmark, was compared with hospital records and information in a pathology system. RESULTS: The analysis of the completeness included 143 patients with Crohn's disease and 285 patients with ulcerative colitis. The completeness of the regional hospital system using the pathology system as a reference standard was 94% for both diseases. The analysis of the validity included 281 patients registered as having Crohn's disease and 506 patients registered as having ulcerative colitis. The validity of the two diagnoses was 97% and 90%, respectively. CONCLUSIONS: The regional hospital system showed few misclassifications of the diagnoses of Crohn's disease and ulcerative colitis. Thus the nationwide hospital system (based on the regional hospital systems) may provide a unique study base for future research.

[Registration in medical journals of prescriptions for strong analgesics prescribed by general practitioners]. / Praktiserende laegers journalregistrering af recepter udstedt på staerke analgetika.

The use of strong analgesics was continuously registered in 90 patients throughout 12 months via the public health authorities, who are responsible for the control of prescription of strong analgesics. After the 12 months, questionnaires were sent to the prescribing doctors about the treatment during that period. Twenty-five patients were excluded mainly due to incomplete data and non-responding GPs. Analysis of validity of the GPs' registration, with the public health authorities' registration used as the reference standard, showed 90% (95% confidence limits (CL):68-99%) agreement concerning continuing treatment with strong analgesics and 98% (CL:88-100%) regarding GPs' registration of patients not being treated with strong analgesics. In all, misclassification occurred in 5% (CL:1-13%) of the patients. Our study suggests that the GPs' information about prescriptions of strong analgesics is valid, and that it can be used in research.

Research in the Danish health service system: completeness and validity of prescription data, illustrated by analysis of utilization of oral anticoagulants.

We studied the utilization of oral anticoagulants and the degree of completeness and validity of some key research variables from the Danish health service in the county of North Jutland (482 000 inhabitants), studying the records of 12 855 prescriptions of oral anticoagulants during 1991 and 1992. The utilization of oral anticoagulants showed an increase of 16% from 1991 to 1992, when 0.3% of all women and 0.4% of all men were treated during one year. The increase was less than expected based on newly introduced indications for treatment of atrial fibrillation. The following variables were studied: the name (ATC commodity number) and amount of the prescribed drug, the defined daily dose, the personal registration number of the patient, type of prescription (e.g. in writing or by telephone), number of repeat prescriptions, date of prescription issued by the doctor, the registration number of the GP or hospital department (if the prescription is made by a hospital doctor) and date of expedition from the pharmacy. The number of wrong and missing data was less than 1%. The study suggests that Danish prescription information is of such quality that it can be used for pharmacoepidemiological studies.

Budesonide versus prednisolone retention enemas in active distal ulcerative colitis.

METHODS: Efficacy and safety of the topically acting glucocorticosteroid budesonide retention enema (2.3 mg/115 mL) were compared with prednisolone disodium phosphate enema (31.25 mg/125 mL) in patients with active distal ulcerative colitis. The study was a randomized, multicentre trial, with two parallel groups and single-blind to the investigator. One hundred patients with active ulcerative colitis, not reaching beyond the splenic flexure as determined by endoscopy, were treated for up to 8 weeks. RESULTS: Forty-five patients were randomized to receive budesonide and 55 to prednisolone. Both treatment groups improved significantly in terms of endoscopic and histological scoring during the study, but there were no statistically significant differences between the two groups. Clinical remission, defined as no more than three daily bowel movements without blood and endoscopically non-inflamed mucosa, was achieved in 16% of the patients in the budesonide group after four weeks and in 24% in the prednisolone group (N.S.). After 8 weeks treatment the clinical remission rate in the groups had increased to 36% for budesonide and 47% for prednisolone (N.S.). Mean morning plasma cortisol levels were unchanged in the budesonide group, whereas they were significantly suppressed in the prednisolone group after 2, 4 and 8 weeks (P < 0.0001). Side effects were mild and rare in both groups. CONCLUSIONS: Treatment with budesonide enema in active distal ulcerative colitis was comparable, regarding efficacy, to treatment with conventional prednisolone enema. A prolongation of the treatment time from 4 to 8 weeks doubled the clinical remission rate in both groups. However, budesonide may be preferable to prednisolone since it causes less systemic effects as reflected by a lack of plasma cortisol suppression.

The diagnostic value of serum urea/creatinine ratio in distinguishing between upper and lower gastrointestinal bleeding. A prospective study.

The predictive value of a urea/creatinine ratio > or = 100 for indicating upper gastrointestinal bleeding was evaluated in 78 consecutive patients with a history of gastrointestinal bleeding 24 hours or less before admission. Serum beta-2-microglobulin was measured to elucidate whether renal hypoperfusion plays a part in elevation of the urea/creatinine ratio. The predictive value of a urea/creatinine ratio > or = 100 in terms of upper gastrointestinal bleeding, was 95% (95% confidence interval (CI): 83-99%), whereas the predictive value of a urea/creatinine ratio < 100, indicating lower gastrointestinal bleeding, was 41% (CI: 25-59%). No statistically significant differences were found between serum beta-2-microglobulin levels in upper and lower gastrointestinal bleeders. We conclude that a urea/creatinine ratio > or = 100 strongly indicates an upper gastrointestinal bleeding source and that the main cause of a high ratio is not renal hypoperfusion.

One-year follow-up after the first prescription of strong analgesics outside hospital.

To evaluate the risk of addiction after prescription of a strong analgesic, we followed 90 patients during the year after they had received a prescription for a strong analgesic for the first time in September 1989 in North Jutland County, Denmark. The study was based on copies of all prescriptions of strong analgesics; these are sent to the National Health Service, which is responsible for the control of the prescribing of strong analgesics. Seven patients were excluded because the data registration was incomplete, while there was valid data on the remaining 83 patients, 12 of whom had cancer. All the cancer patients and 14 other patients died during the follow-up period. Of the remaining 57 patients, seven were still being treated (12.3%; 95 confidence limits: 5.1-23.7%) with strong analgesics. Addiction was not suspected by their general practitioners in any of these seven as the main reason for continued treatment with strong analgesics. We therefore conclude that addiction is rare after a first prescription of strong analgesics.

The reference range for complexed alpha 2-macroglobulin human plasma: development of a new enzyme linked in immunosorbent assay (ELISA) for quantitation of complexed alpha 2-macroglobulin.

Purified alpha 2-macroglobulin was complexed by reaction with methylamine and used to raise monoclonal murine antibodies. A four-step enzyme linked immunosorbent assay (ELISA) was developed to determine the antibody-specificity of the produced monoclonal murine antibodies towards human native and complexed alpha 2-macroglobulin. Two monoclonal antibodies were selected, H11A11 (specific towards complexed alpha 2-macroglobulin) and 1CG4 (recognizes both forms of the molecule), and purified by affinity chromatography on protein G. The purified antibodies were used to develop a fast three-step ELISA for exact quantitation of complexed and total alpha 2-macroglobulin in human plasma. The intra-assay coefficient of variation (CV) for measurement of complexed alpha 2-macroglobulin is 2.2-9.9%, whereas the inter-assay CV was determined to be 3.7-10.5% and the recovery of the assay is 93-108%. The assay for total alpha 2-macroglobulin has an intra-assay CV of 3.0-15.5%, an interassay CV of 5.1-21.2% and a recovery of 91-116%. Citrated plasma samples from 139 healthy blood donors were examined, resulting in a reference range for complexed alpha 2-macroglobulin of 13.5-31.1 mg 1(-1) with a median value of 21.7 mg 1(-1). The concentration of total alpha 2-macroglobulin was measured by the same assay using the monoclonal antibodies 1CG4. For total alpha 2-macroglobulin we determined the reference range to be 1.12-3.54 g 1(-1) with a median value of 2.14 g 1(-1). Based on these results the reference range for complexed alpha 2-macroglobulin as a percentage of total alpha 2-macroglobulin was calculated to be 0.8-1.9% with a median value of 1.0%.

Diagnostic problems with meningococcal disease in general practice.

Based on general practitioners' referral letters and hospital records, we made a retrospective analysis of a cohort of 177 consecutive cases of meningococcal disease that occurred during a period of 10 years in the County of North Jutland, Denmark. The analysis concerned diagnostic problems in general practice, prognosis, pre-hospital antibiotic treatment and its effect on subsequent cultures, and degree of obligatory notification. The referring doctor suspected meningococcal disease/central nervous infection in 123 patients (69.5%). Neck stiffness and petechiae were related to a correct referral diagnosis, in contrast to the occurrence of a non-petechial rash. The presence of disseminated intravascular coagulation was associated with the mortality rate, which was 0.062. The therapeutic recommendations of the Danish Health Authorities were followed in only 25 of the 98 patients who fulfilled the criteria for pre-hospital parenteral antibiotic treatment. Pre-hospital antibiotic treatment was related to negative culture of spinal fluid or blood. Seven of the 177 patients were not notified according to the rules. Difficulties in pre-hospital diagnosis seem not to influence the lethal course of the disease.

Epidemiology of pain requiring strong analgesics outside hospital in a geographically defined population in Denmark.

Based on obligatory notifications from pharmacies to the National Board of Health about prescription of strong analgesics as well as questionnaires to the prescribing doctors, the occurrence and causes of pain requiring strong analgesics outside hospitals were analysed over a period of one month in Denmark in a limited population (480,000), corresponding to nearly 10% of the Danish population. During one month, strong analgesics were prescribed to 0.2 per cent of the population. The commonest acute conditions were back pain (23%) and trauma (17%). The commonest recurrent acute conditions were headache (25%) and angina pectoris (17%). The commonest chronic non-malignant conditions were back pain (29%) and pancreatitis (7%). The commonest malignant conditions were lung cancer (20%) and colorectal cancer (14%). The commonest conditions indicated under the chronic pain syndrome were headache (33%) and back pain (13%). Conditions requiring strong analgesics reflect to some extent the distribution of painful conditions in the general population.

Overall use of proctoscopy in general practice and possible relation to the stage of rectal cancer.

Data from the Danish National Health Service records on activities of each of 146 general practices in the county of North Jutland, Denmark, were studied to determine whether the use of proctoscopy influenced the stage at which cancer of the rectum was recognized. Information for all patients in the county who received the diagnosis of cancer of the rectum was obtained from the Danish Cancer Registry. Proctoscopy was performed significantly more often in partnership practices (96%) than in single practices (81%). The frequency with which the test was used varied from 1 to 107 proctoscopies per general practitioner per year. In the 95 patients with cancer of the rectum, no relationship was found between the stage (Dukes') at the time of diagnosis and work-load, size and activity of practice, or use of proctoscopy.

Bacterial meningitis in elderly patients: clinical picture and course.

We reviewed the case records of 48 patients aged 60 years and older with a diagnosis of acute bacterial meningitis made during the period 1976-88. Predisposing conditions were present in 26 patients (54%) and concurrent infections in 24 patients (50%). Streptococcus pneumoniae accounted for 41% of all isolates and 56% were Gram-positive organisms. The most common symptoms were fever (79%), meningism (54%) and change in mental status (69%). Sixty-three per cent of the patients survived. Increased fatality was associated with absence of typical symptoms and signs and was presumably due to a delay in diagnosis. Other clinical and biochemical variables and antimicrobial therapy before admission to hospital and the presence of underlying disease were not associated with outcome.

A prospective multipractice study based on antecedent data. Reduced selection and behaviour bias.

A prospective multipractice study based on well-defined data collected by a number of general practitioners (GPs) over a period of time is often used in primary health care research. However, problems of research methodology such as selection bias are common in such studies when GPs either refuse to participate or interrupt their participation. A method is described whereby selection bias is avoided. In the present study, a medical laboratory made a daily record of all abnormal liver function tests requested by GPs over a period of six months. When mailing these results to the GPs, a questionnaire was enclosed in order to obtain a number of clinical data from them. Thirty of 31 possible GPs participated. During the study period, questionnaires concerning 134 patients were mailed, and 118 of these were returned without reminders. Following one reminder the response rate was 100%. Comparing the number of requested tests during the study period with the number requested during a control period before and after the study period (same six month periods of the year), no difference was seen in the pattern of requests. Thus, this method, unbiased with respect to both selection and request-behaviour, is recommended for similar studies.

Epidemiology of abnormal liver function tests in general practice in a defined population in Denmark.

It is common for general practitioners (GPs) to refer patients suspected of impaired liver function for laboratory tests (alkaline phosphatase, lactate dehydrogenase, bilirubin, prothrombin, aspartate aminotransferase). In a prospective multipractice study over a six-month period, including 30 GPs, 55 patients were recorded as having, for the first time, a high level of alkaline phosphatase (AP) as an isolated finding, 14 with an increase of aspartate aminotransferase (ASAT), eight with an increase of both AP and ASAT, three with an increase of ASAT, AP, and bilirubin, two with an isolated increase of lactate dehydrogenase (LDH), one with an increase of ASAT, AP, and bilirubin, combined with a low prothrombin (PP), and, finally, one patient with a low prothrombin in isolation. In most cases the tests were requested because of unspecific symptoms. The most common causes of abnormal test results were neoplasms, alcoholic liver disease, and heart failure. Thirty patients were referred to hospital for further investigations. During the same study period, 50 patients with known abnormal liver function tests were recorded, and the most common causes of these abnormalities were neoplasms, rheumatoid arthritis, and alcoholic liver disease.

Xanthine and hypoxanthine in amniotic fluid during pregnancy.

Xanthine and hypoxanthine are indicators of cellular hypoxia. The purpose of our study was to establish a reference range for the concentrations of xanthine and hypoxanthine in amniotic fluid. Of a total of 38 included in the investigation, 27 pregnant women were found to have low values for xanthine (less than 1.2 mumol/l) and hypoxanthine (less than 0.4 mumol/l). To our knowledge, this is the first attempt to define a reference range for xanthine and hypoxanthine concentration in amniotic fluid during pregnancy.