General Hospital Laboratory Research Articles

Prevalence of sexually transmitted diseases (STDs) in Owerri, Nigeria

Medical records of two health institutions in Owerri ‐ Owerri General Hospital and Avigram Medical Diagnostic and Research Laboratories ‐ were examined between 1990 and 1993 to determine the extend and types of sexually transmitted diseases in Owerri. Sexually transmitted diseases recorded in both centers were trichomoniasis, candidiasis, gonorrhoea, and syphilis. The cases of confirmed STD at the General Hospital Owerri nearly doubled from 77 in 1990 to 144 in 1993. For the Avigram Medical Laboratories the figures almost tripled 134 and 367 for 1990 and 1993 respectively. Data analysis of the cases confirmed at the Owerri General Hospital and Avigram Medical Laboratories gave no significant difference between the two institutions at the 95% level of confidence.

Glycemic control in diabetes mellitus: have changes in therapy made a difference?

New methods of measuring and controlling glycemia in diabetes mellitus have been developed and implemented in the past 10 years. We examined whether glycemia, as measured by glycosylated hemoglobin, changed in outpatient insulin-dependent diabetes mellitus (IDDM) and noninsulin-dependent diabetes mellitus (NIDDM) populations between 1985 and 1993 and whether contemporaneous changes in therapy could account for observed changes in glycemia. Outpatients were selected based on having glycated hemoglobin (HbA1c) measured in the Massachusetts General Hospital laboratory during March 1985 (IDDM n = 94 and NIDDM n = 137) or during March 1993 (IDDM n = 89 and NIDDM n = 118). Chart reviews established demographic and clinical characteristics, including frequency of blood glucose self-monitoring, insulin injections, office visits, and HbA1c measurements during the year prior to the HbA1c result. Mean HbA1c level was significantly lower in the 1993 IDDM cohort compared with the 1985 cohort (8.77% +/- 1.7% versus 9.47% +/- 2.1%, P = 0.014). In the NIDDM cohorts, the difference in mean HbA1c did not achieve statistical significance (8.35% +/- 1.6% in 1993 versus 8.75% +/- 2.1% in 1985, P = 0.09); however, when adjusted for differences in NIDDM duration, HbA1c in the 1993 cohort was significantly lower than that in the 1985 cohort. The largest decrease in HbA1c in NIDDM was in patients treated with insulin (9.53% +/- 2.0% versus 8.54% +/- 1.5% in 1985 and 1993, respectively, P = 0.004). Multiple linear regression analyses demonstrated that increased frequency of self-monitoring and of insulin injections were associated with lower HbA1c in IDDM. The level of average glycemia has decreased in IDDM patients over the past 8 years, attributable, at least in part, to an increased frequency of monitoring and of insulin injections. Glycemia decreased in NIDDM, especially in the subset of patients treated with insulin. This temporal shift in glycemic control should have a salutary effect on the development of long-term microvascular and neurologic complications.

The design of small radiopharmacetical preparation facilities

Sunderland District General Hospital, Sunderland and Stockton Pharmaceutical Quality Control Laboratory, Stockton, UK

DAILY MOVEMENT, ABDOMINAL ADIPOSITY, AND BLOOD GLUCOSE IN A COMMUNITY SAMPLE OF OLDER ADULTS.

New Britain General Hospital, New Britain, CT and JB Pierce Laboratory and Yale University, New Haven, CT.

Locally challenging osteo- and chondrogenic tumors of the axial skeleton: Results of combined proton and photon radiation therapy using three-dimensional treatment planning

Tumors of the axial skeleton are at high risk for local failure. Total surgical resection is rarely possible. Critical normal tissues limit the efficacy of conventional photon therapy. This study reviews our experience of using combined high dose proton and photon radiation therapy following three-dimensional (3D) treatment planning. Between December 1980 and September 1992, 47 patients were treated at the Massachusetts General Hospital and Harvard Cyclotron Laboratory for primary or recurrent chordomas and chondrosarcomas (group 1, 20 patients), osteogenic sarcomas (group 2, 15 patients) and giant cell tumors, osteo-or chondroblastomas (group 3, 12 patients). Radiation treatment was given postoperatively in 23 patients, pre- and postoperatively in 17 patients, and 7 patients received radiation therapy as definitive treatment modality following biopsy only. The proton radiation component was delivered using a 160 MeV proton beam and the photon component using megavoltage photons up to 23 MV energy with 1.8-2.0 Cobalt Gray Equivalent (CGE) per fraction, once a day. Total external beam target dose ranged from 55.3 CGE to 82.0 CGE with mean target doses of 73.9 CGE (group 1), 69.8 CGE (group 2), and 61.8 CGE (group 3). Group 1 (chordoma and chondrosarcoma): Five of 14 patients (36%) with chordoma recurred locally, and 2 out of 5 patients developed distant metastasis, resulting in 1 death from disease. A trend for improved local control was noted for primary vs. recurrent tumors, target doses > 77 CGE and gross total resection. All patients with chondrosarcoma achieved and maintained local control and disease-free status. Five-year actuarial local control and overall survival rates were 53% and 50% for chordomas and 100% and 100% for chondrosarcomas, respectively. Group 2 (osteogenic sarcoma): Three of 15 patients (20%) never achieved local control and died within 6 months of completion of radiation treatment. Only 1 out of 12 patients who were controlled for more than 6 months failed locally, yielding a 5-year local control rate of 59% for 15 patients. Overall, 4 patients (27%) developed distant metastasis (two in patients with uncontrolled primary); 4 patients succumbed to their disease, 3 patients died of intercurrent disease, resulting in overall survival of 44% at 5 years. Group 3 (giant cell tumors, osteo- and chondroblastoma): One of 8 patients with giant cell tumor failed locally, 1 patient distantly, and all patients are alive. Three of 4 patients with osteo- or chondroblastoma are alive and well. One patient suffered local recurrence and died of disease. Local control rate and overall survival for this group of 12 patients was 76% and 87% and local control for patients with giant cell tumors 83% at 5 years. In the majority of cases radiotherapy was well tolerated. However, one patient with a large base of skull tumor developed retinopathy, one patient required enucleation of a previously blind eye, and another patient with sacral tumor developed chronic diarrhea. Combined proton and photon radiation therapy optimized by 3D treatment planning, allows the delivery of higher radiation doses to tumors of the axial skeleton, while respecting normal tissue constraints. High radiation doses can result in improved long-term local control.

Cost control of out-of-hours laboratory services in district general hospitals.

To survey methods for cost control of out-of-hours laboratory services in district general hospitals in England and Wales. A questionnaire was distributed to 66 district general hospital laboratories in England and Wales. The response rate was 61%. Most laboratories for which budgetary information was provided had on-call costs ranging between 10-21% of staff costs. Ninety five per cent of respondents had attempted to reduce workload by the use of various strategies. Seventy two per cent of responding laboratories had negotiated a wide variety of on-call agreements outside Whitley Council arrangements. Seventy two per cent were not satisfied with their on-call arrangements, the main desired objective being the introduction of the extended working day. From this study it seems that Whitley Council agreements for out-of-hours work are no longer appropriate for the average district general hospital laboratory. Workload reduction strategies should include the use of a limited list, audit of the use of the on-call service, and continued education of medical staff. Consideration may also be given to the introduction of fixed payments, extension of the working day, increased multidisciplinary on-call and increased bedside testing.

Apolipoprotein E and its receptor LRP in AD and control brain : GW Rebeck, SD Harr, DK Strickland and BT Hyman. Dept of Neurology, Mass. General Hospital, Boston, MA 02114 and Biochemistry Laboratory, American Red Cross, Rockville, MD 20855

Apolipoprotein E and its receptor LRP in AD and control brain : GW Rebeck, SD Harr, DK Strickland and BT Hyman. Dept of Neurology, Mass. General Hospital, Boston, MA 02114 and Biochemistry Laboratory, American Red Cross, Rockville, MD 20855

Thyroid hormones in human follicular fluid and thyroid hormone receptors in human granulosa cells

To demonstrate the presence of thyroid hormone in human follicular fluid (FF) and the binding of antithyroid hormone antibodies in human granulosa cells (GCs). Follicular fluids and GCs collected from women undergoing oocyte retrieval after superovulation. In Vitro Fertilization-America/Allegheny General Hospital and Reproductive Sciences Research Laboratories, the Department of Obstetrics and Gynecology, The Medical College of Pennsylvania/Allegheny Campus. Follicular fluid levels of triiodothyronine (T3) determined by a microparticle enzyme immunoassay and FF levels of thyroxine (T4) determined by a fluorescence polarization immunoassay. Three anti-thyroid receptor antibodies were used to determine the presence of thyroid receptor. The binding of these antibodies in GCs was assessed by fluorescent microscopy and flow cytometry. Both T3 and T4 were present in the FF of eight patients studied. A large majority of the samples of individual fluids fell within the normal range for serum. There was a positive correlation between serum T4 values and FF T4 values. The three antithyroid receptor antibodies showed positive nuclear staining of GCs by fluorescent microscopy. The antibody to all thyroid hormone receptors yielded 35% positive cells by flow cytometry, and the site specific antibody for either the alpha-1 or beta-1 receptors yielded 78% and 44% positive cells, respectively. These data demonstrated, for the first time, the presence of T3 and T4 in human FF and the presence of T3 binding sites in human GCs and suggest a role for thyroid hormone in the regulation of human GCs.

Invasive disease due to Salmonella virchow: a North Queensland problem

Salmonella virchow is the second most commonly isolated salmonella serotype from human sources in Australia, and overseas studies indicate that S. virchow is a significant cause of extraintestinal salmonellosis. The successful management of three infants, two with septicaemia and one with leptomeningitis and septicaemia due to S. virchow, is described. A review of the Townsville General Hospital laboratory records (1978-1988) showed that, among other aspects, S. virchow accounted for 46% of all salmonella septicaemias, further exemplifying the invasive propensity of this serotype. Information obtained from various sources, after crude analyses, demonstrates that more than 90% of S. virchow infections in humans in Australia occur in Queensland, and that most (greater than 78% in 1987) of those infections in Queensland come from a coastal zone north of Bundaberg, with the highest concentration (0.4 per 1000 persons) occurring in the Cairns region.

A modified indirect fluorescent antibody test for the diagnosis of brucellosis

We adapted the conventional indirect fluorescent antibody (IFA) test to assay IgM and IgG Brucella-specific antibodies to differentiate acute from chronic infections rather than measure total antihuman globulin specific antibodies. The results were compared with the slide agglutination test (SAT) used for screening and the quantitative microagglutination test (MAT). Of a total of 118 randomly selected samples sent for anti-Brucella antibodies received at a general hospital laboratory, 58 (47.9%) were found to be positive for IFA-IgG test but not necessarily by other tests. Eleven of these cases were positive for Brucella melitensis by culture. Sixty serum samples found negative for Brucella antibodies by IFA and other tests were of patients with medical conditions other than brucellosis. Fifty serum samples from healthy blood donors were negative for Brucella spp. antibodies by all the three tests. The IFA test was found to be a more sensitive test than MAT and distinguished an acute infection from chronic disease.

Limitations of Chlamydiazyme in general hospital laboratories.

Limitations of Chlamydiazyme in general hospital laboratories.

Economy and efficiency in routine thyroid-function testing: use of a sensitive immunoradiometric assay for thyrotropin in a general hospital laboratory.

We measured thyrotropin (TSH) with a sensitive immunoradiometric assay (IRMA) in 2329 consecutive serum samples received for thyroid-function tests from hospital and general practice. Of these, 185 (7.9%) had TSH values less than 0.2 milli-int. unit/L: 33 (1.4%) were hyperthyroid, 20 (0.9%) were being treated for hyperthyroidism, 115 (4.9%) were receiving L-thyroxin, and 17 (0.7%) were clinically euthyroid but had severe non-thyroidal illnesses. In the first 506 serum samples, we also measured free thyroxin, free triiodothyronine (FT3), and total thyroxin. Thyroliberin (thyrotropin-releasing hormone, TRH) tests performed on 84 patients showed that an undetectable initial TSH (usually ascribable to therapy with thyroxin) predicted a flat TRH response. All untreated thyrotoxic patients had undetectable TSH. Experience confirmed that this TSH assay, in conjunction with a supplementary assay of FT3 when the TSH concentration is less than twice the limit of detection, is efficient and economical for routine evaluation of thyroid function in an unselected population.

Rapid measurement of anticonvulsant drug concentrations in the out-patient clinic, using HPLC with direct injection of plasma.

A manual column-switching technique is described for the measurement of phenytoin, phenobarbitone, carbamazepine, and carbamazepine 10,11-epoxide. The analytical system is designed to be portable for use at the out-patient clinic and comprises an isocratic pump, UV detector and injection valve, together with a preparation column. Diluted plasma or serum is injected, without pre-extraction, onto a preparation column which replaces the sample loop on the injection valve. After washing unwanted material to waste, the preparation column is switched in-line with the analytical column, where separation of analytes occurs. The precision, accuracy and carryover of this extra-laboratory system are comparable with those obtained with laboratory-based immunoassay systems. Operation of the system allows the reporting of results within 5 min of sample injection and requires no specialist skills. The technique should be of particular interest to district general hospital laboratories where workload does not justify the cost of an automated HPLC system as the total capital cost is comparable to that of a portable glucose analyser. In contrast to immunoassay systems consumable costs are minimal. The equipment is easy to transport and may be used in the out-patient department to provide an analytical service similar to that provided for the determination of prothrombin time at the anticoagulant clinic.

Circulating immunocomplexes in the diagnosis of autoimmune and neoplastic disorders: new perspectives.

Two new competitive immunoenzymatic assays ("C.I.C.-conglutinin" and "C.I.C.-C1q") were employed to evaluate circulating immunocomplexes in 90 patients with a variety of autoimmune and neoplastic disorders. In autoimmune diseases the assays appeared very sensitive and relatively concordant, while in malignancies sensitivity was high with the C.I.C.-conglutinin method but much lower with the C.I.C.-C1q method. The clinical significance of these results is discussed with particular regard to the possibilities of application of the two assays in the diagnostic routine of a general hospital laboratory.

Neuroleptic drug level monitoring in psychiatry: focus on radioreceptor assay techniques.

Preliminary studies with the radioreceptor assay for neuroleptics suggest several advantages of this technique. Consistent with results obtained with other techniques, it is obvious that there is variation among individuals in terms of the serum levels obtained on given oral doses of neuroleptics; in addition, total daily dose correlates poorly with serum levels. The radioreceptor assay technique, however, is relatively uncomplicated and inexpensive and relies on methods that are commonly used in general hospital laboratories. Unlike gas chromatography/mass spectrometry, gas-liquid chromatography, and even radioimmunoassay--which are highly discriminative--the radioreceptor assay detects both parent drugs and active metabolites of virtually all classes of neuroleptics on the basis of their presumed physiologic mechanism of action.

A community hospital laboratory computer system: an eight-year longitudinal study of economic impact.

An analysis of the intralaboratory economic effects of installation of a dedicated laboratory computer system in a 450-bed acute care general hospital laboratory is presented using data accumulated during an eight-year period. Data collection and analytic conventions used included: (1) an inflation factor derived from the CPI to adjust costs; (2) semilogarithmic plotting; (3) patient procedure counts tallied as the raw count for patient specimens according to the CAP Workload Recording Method; and (4) total workload (including patient standard and control items) recorded according to the CAP WRM. The authors conclude that computerization has produced: (1) a decrease in inflation adjusted labor costs per unit of work; (2) a decrease in inflation adjusted direct cost per unit of work; (3) A decline in the ratio of clerical to technical labor force; and (4) An increase in overall productivity of approximately 7%.

Laboratory differentiation of hypercalcemic patients.

We studied the biochemical discrimination of primary hyperparathyroidism from other causes of hypercalcemia. This potentially serious disorder is readily remedied, and because recent work has suggested that even very mild cases in elderly people derive substantial benefit from surgery, the correct diagnosis is crucial. A discriminant function is derived that maximizes the use of data that are readily available from general hospital laboratory; application of the Hamilton "T score" system simplifies its interpretation. We conclude that the best use of this formula is as a negative discriminant, to identify some non-hyperparathyroid cause of hypercalcemia, and also as a partial positive discriminant, to identify some cases of primary hyperparathyroidism. We review previous such discriminants and consider the reasons why they have been less successful.

Factors Influencing Diazepam Pharmacokinetics

Clinical Pharmacology Unit, Massachusetts General Hospital and Psychopharmacology Research Laboratory, Massachusetts Mental Health Center, Boston, Massachusetts

Salmonellosis in Hong Kong

An analysis of the incidence of enteric fever and the prevalent salmonella serotypes isolated at a Public Health Laboratory and a General Hospital Laboratory in Hong Kong for the years 1965–74 is reported. The results were compared with those obtained in 1953–64 by Huang & Teoh-Chan. 1 Although the annual incidence of enteric fever showed some variations, it is on the whole declining. On the over hand, the isolations of gastroenteric salmonella serotypes showed a striking increase. The probable causes of the change have been discussed. The salmonella serotypes most commonly isolated are listed together with the numbers of isolations from faecal and non-faecal specimens. The age distribution, seasonal variation and annual incidence are also shown.

Evaluation of serum ionic calcium measurement in a general hospital population.

Direct measurement of ionic calcium was evaluated in light of conflicting reports concerning the correlation of ionic calcium with total calcium and ionic calcium as predicted from total calcium and serum protein. Ionic calcium in the sera of normo- hypo-, and hypercalcemic adult hospitalized patients was measured anaerobically using an Orion model 98-20 calcium flow-thorugh electrode. Good correlation (r = .77) was found with the calculated ionic calcium value derived from total protein and total calcium, using the McLean-Hastings nomogram. Good correlation was also present between the measured ionic and total calcium (r = .80). In view of these correlations, the introduction of serum ionic calcium measurements into the general hospital laboratory repertoire is of questionable value.