Haematological and biochemistry laboratory abnormalities associated with splenomegaly in asymptomatic adults in Masaka, Uganda: implications for HIV biomedical prevention trials

Objectives  To assess the degree of haematological and biochemistry abnormalities associated with splenomegaly in asymptomatic adults in order to determine whether they may be eligible for inclusion in HIV biomedical prevention trials.
Methods  Asymptomatic adults (50% women) aged 18–60  with splenomegaly (≥grade II by Hackett's classification) who agreed to provide blood and urine specimens for laboratory testing were invited to participate in a cross-sectional study. Volunteers who were menstruating, pregnant, infected with HIV, syphilis or Hepatitis B and C, or had significant clinical findings were excluded. Haematological and biochemistry laboratory evaluations were performed for enroled volunteers, and the results were compared to local reference ranges. The proportion of volunteers with out-of-range (OOR) values was estimated for each parameter. Linear regression models were fitted to investigate the association between grade of splenomegaly and laboratory values.
Results  The proportion of volunteers with OOR haematology values ranged from 4.5% (mean corpuscular volume) and 15% (CD4 cells) to 31% (basophils). Increasing spleen size was significantly associated with anaemia, thrombocytopenia and low CD4 count. OOR biochemistry values were found in about 10% of volunteers. Increasing spleen size was associated with reduced creatinine phosphokinase and creatinine (in men) and raised lactate dehydrogenase.
Conclusions  In areas with a high prevalence of splenomegaly, most asymptomatic individuals with this condition have haematology and biochemistry values that fall within the local reference ranges, and they could therefore be eligible for inclusion in HIV biomedical prevention trials. However, the effect of splenomegaly on certain parameters should be taken into account during interpretation of laboratory-based adverse events.     

Accuracy of the hemocue portable glucose analyzer in a large nonhomogeneous population

Several studies have reported inconsistent results between HemoCue (HC) whole blood glucose measurements compared to plasma glucose. We selected a large patient population with diverse pathologies and healthy volunteers to evaluate HC. For this comparison, whole blood glucose concentration was measured using HC and referenced to laboratory plasma glucose. The population (n = 512) included healthy volunteers, diabetics, and patients with heart failure, liver failure, renal failure, renal and liver transplant, and other chronic diseases. Patients were on a wide variety of medications, vitamins, and food supplements. Venous blood samples were collected in tubes containing potassium oxalate and sodium fluoride. Comparison of the results was made using the method of Bland and Altman and ANOVA at three selected glucose ranges. The glucose measurement ([HC + laboratory]/2) ranges were 24-75, 76-129, and 130-404 mg/dL. A positive bias for all three glucose ranges was observed: 38 +/- 17 mg/dL for the high glucose group compared to 24 +/- 9 mg/dL and 22 +/- 10 mg/dL for the middle and low groups, respectively. In the high glucose group 90% of the values were within 10% (R = 0.97) of the laboratory reference values compared to 81% and 55% in the normal and low glucose groups, respectively. HC glucose measurements were generally within two SD from the laboratory plasma reference. HC consistently yielded lower whole blood glucose measurements than plasma with the largest differences seen in the low glucose range (29%). HC measured more consistently at the higher glucose concentrations and was 16% lower than plasma, although the mean absolute error was highest for that range. No significant effects in the bias could be attributed to disease while possible effects from instrument modifications by the manufacturer remain uncertain.     

Characteristics of a population volunteering for human immunodeficiency virus immunization. NIAID AIDS Clinical Trials Network

A total of 166 volunteers for an AIDS vaccine study (Vaxsyn, baculovirus produced recombinant GP160; MicroGeneSys Inc, West Haven, Connecticut, USA) were interviewed and examined. Blood was collected for routine laboratory testing as well as T-cell counts, HIV ELISA (EIA), Western blot (WB) and p24 Ag. Eighty-five men (mean age 22.2 years, range 18-42) and 81 women (mean age 23.9 years, range 17-50) volunteered; 130/166 (78%) were university students. Most had learned of the study from news media (55%), friends or workplace (37%). The most common causes for exclusion were the presence of indeterminate WB (26.5%) or a change of mind after the initial interview (24%). Other causes were abnormal cell count and differential (7.2%), elevated alanine aminotransferase (3.6%), positive hepatitis B antibody (3.6%), abnormal urinalysis (3.4%), recent venereal disease (3.0%), T4 cell count less than 400 (1.9%), abnormal chest X-ray (1.7%), recognized high-risk behaviour (1.7%), multiple sex partners (1.2%), positive rapid plasma reagin test (1.2%), failure to meet age criteria (1.2%), unable to be available for entire study (1.2%), abnormal physical examination (0.6%) and positive p24 Ag (0.6%). No volunteers had positive EIA, but 14.5% had more than one reason for exclusion. Even in a community with low prevalence for HIV, a large majority of healthy heterosexual volunteers can be expected to be ineligible for enrollment in HIV vaccine trials. An average of 4.8 volunteers were screened for each of 12 vaccinees chosen.     

五种驱避剂对亚历山大白蛉效果的研究

1986～1987年在新疆吐鲁番市煤窑沟,首次应用5种驱避剂对当地传播黑热病媒介野栖的亚历山大白蛉,进行了室内和野外驱蛉效果试验。实验室所用雌性白蛉3301只,野外受试者306人次。当剂量为0.25μl/cm~2时,液剂的驱蚊露(MRP)、N’N-二乙基间甲苯甲酰胺(DETA)、蚊怕水(MRL)、邻苯二甲酸二甲酯(DMP)和邻苯二甲酸二丁酯(DBP)的保护时间分别为7.5h、5h、3.75h、1.25h和1h;剂量为0.75mg/cm~2时,清凉油剂的DETA、DMP和DBP的保护时间分别为5.5h、3.5h和3h。实验室和野外驱蛉效果相一致。5种驱避剂的效果依次为MRP>DETA>MRL>DMP>DBP。5种驱避剂对皮肤无任何副作用,使用方便。这对保护野外作业人员,具有实用意义。     

Esophageal mucosal acid sensitivity can coexist with normal pH recording in healthy adult volunteers

We aimed to determine whether healthy volunteers with normal pH monitoring study results experienced heartburn or discomfort during an esophageal acid perfusion test. We performed an esophageal acid perfusion test, followed by ambulatory esophageal pH monitoring, in 15 healthy and asymptomatic volunteers (aged 19 to 34 years). The results of the acid perfusion test were correlated with those of the pH monitoring. Three subjects (20%) reported chest discomfort during acid perfusion. The pH data in all subjects were within our laboratory reference ranges; the median (range) percent total time at pH < 4 being 1.7 (0.2–4.0)% [laboratory reference, median (range), 3.0 (0.2–4.0)%]. We concluded that direct infusion of acid onto the distal esophagus can produce discomfort akin to that of gastroesophageal reflux disease in asymptomatic adult volunteers, even in the absence of excessive esophageal acid exposure. Received: July 2, 1999 / Accepted: October 22, 1999     

Radioimmunoassay and tandem mass spectrometry measurement of bedtime salivary cortisol levels: a comparison of assays to establish hypercortisolism

CONTEXT: Although bedtime salivary cortisol measurement has been proposed as the optimal screening test for the diagnosis of Cushing's syndrome, its performance using commercially available assays has not been widely evaluated. OBJECTIVE: Our objective was to compare RIA and tandem mass spectrometry (LC-MS/MS) measurement of salivary cortisol in obese subjects and healthy volunteers. DESIGN AND SETTING: We conducted a cross-sectional prospective study of outpatients. SUBJECTS AND METHODS: We studied 261 obese subjects (186 female) with at least two additional features of Cushing's syndrome and 60 healthy volunteers (30 female). Subjects provided split bedtime salivary samples for cortisol measurement by commercially available RIA and LC-MS/MS. Results were considered normal or abnormal based on the laboratory reference range. Subjects with abnormal results underwent evaluation for Cushing's syndrome. RESULTS: In paired samples, RIA gave a lower specificity than LC-MS/MS in obese subjects (86 vs. 94%, P = 0.008) but not healthy volunteers (86 vs. 82%, P = 0.71). Among subjects with at least one abnormal result, both values were abnormal in 44% (confidence interval 26-62%) of obese and 75% (confidence interval 33-96%) of healthy volunteers. In obese subjects, salivary cortisol concentrations were less than 4.0 to 643 ng/dl (<0.11-17.7 nmol/liter; normal, < or =100 ng/dl, 2.80 nmol/liter) by LC-MS/MS and less than 50 to 2800 ng/dl (1.4-77.3 nmol/liter; normal, < or =170 ng/dl, 4.7 nmol/liter) by RIA. Cushing's syndrome was not diagnosed in any subject. CONCLUSION: Salivary cortisol levels should not be used as the sole test to diagnose Cushing's syndrome if laboratory-provided reference ranges are used for diagnostic interpretation.     

Anti-cyclic citrullinated peptide antibodies in scleroderma patients

Anti-CCP (cyclic citrullinated peptide) is considered the most useful laboratory tool in the diagnosis of rheumatoid arthritis (RA). Some authors have also found this autoantibody in patients with scleroderma (SSc). The study aimed to investigate the prevalence of anti-CCP antibodies in SSc patients from Southern Brazil and their association with clinical and serological profile of the disease. We studied 76 patients with SSc and 100 healthy volunteers for presence of anti-CCP. SSc patients charts were reviewed for clinical and laboratory data. In the SSc group, the diffuse form was present in 20.5%; 62.8% had the limited form; 14.1% had overlap with systemic lupus or polymyositis and 2.5% had SSc sine scleroderma. Anti-CCP was found in nine of 78 (11.5%) SSc patients and in one of 100 healthy volunteers (p = 0.0054). No relationship was found with arthritis, skin Rodnan m score, esophageal dysmotility, myocarditis, pulmonary hypertension and lung fibrosis. Positive association was observed with arthralgias (p = 0.02). Also, no relationship was noted with the presence of anti-centromere antibodies, anti-Scl-70, anti-RNP or rheumatoid factor. Anti-CCP are more common in SSc patients than in controls. Arthralgias but not arthritis or rheumatoid factor are more frequent in anti-CCP positive patients.     

The effect of CS-514, an inhibitor of HMG-CoA reductase, on serum lipids in healthy volunteers

CS-514 is a competitive inhibitor of HMG-CoA reductase. The effect of this agent on serum lipids and lipoproteins was studied in 10 healthy normocholesterolemic male volunteers by giving 20 mg of CS-514 or placebo twice a day for 7 days under double-blind conditions. The mean total serum cholesterol level decreased by 18.6% in the CS-514 group, whereas it increased by 7.4% in the placebo group and the difference between the two groups was statistically significant (P less than 0.01). LDL cholesterol and LDL apo B values were reduced by 22.6% and 23.2%, respectively. Serum triglyceride level did not change significantly. No clinical or laboratory abnormalities were observed.     

Increased Blood Acetate: A New Laboratory Marker of Alcoholism and Heavy Drinking

Blood acetate concentration of 51 intoxicated patients was measured and compared to conventional laboratory markers of chronic alcoholism. Mean blood acetate concentration of 23 chronic alcoholics and 17 heavy drinkers was significantly (p less than 0.0005) higher than that of 53 nonalcoholic volunteers or 11 occasional drinkers. Blood acetate level was completely independent of blood ethanol concentration ranging from 0.20 to 2.90 promille. Blood acetate was elevated in 65% of both chronic alcoholics and heavy drinkers. Gammaglutamyltransferase was abnormal only in 35%, aspartate aminotransferase in 21% and mean corpuscular volume in 12% of heavy drinkers. Combination (acetate + gammaglutamyltransferase) correctly detected 87% of alcoholics and 71% of heavy drinkers. During ethanol oxidation the upper normal limit of blood acetate is 0.75 mM. The specificity of increased blood acetate is as high as 92%. Increased blood acetate is indicative for metabolic tolerance to alcohol and it may be so far the most sensitive and specific laboratory marker of chronic alcoholism and heavy drinking.     

Within- and between-laboratory precision in the measurement of body volume using air displacement plethysmography and its effect on body composition assessment

OBJECTIVE: To determine and compare the extent of within- and between-laboratory precision in body volume (BV) measurements using air displacement plethysmography (ADP), the BOD POD body composition system, and to interpret any such variability in terms of body composition estimates. DESIGN: Repeated test procedures of BV assessment using the BOD POD ADP were reproduced at two laboratories for the estimation of precision, both within and between laboratories. SUBJECTS: In total, 30 healthy adult volunteers, 14 men (age, 19-48 y; body mass index (BMI), 19.7-30.3 kg/m2) and 16 women (age, 19-40 y; BMI, 16.3-35.7 kg/m2), were each subjected to two test procedures at both laboratories. Two additional volunteers were independently subjected to 10 repeated test procedures at both laboratories. MEASUREMENTS: Repeated measurements of BV, uncorrected for the effects of isothermal air in the lungs and the surface area artifact, were obtained using the BOD POD ADP, with the identical protocol being faithfully applied at both laboratories. Uncorrected BV measurements were adjusted to give estimates of actual BV that were used to calculate body density (body weight (BWt)/actual BV) from which estimates of body composition were derived. The differences between repeated BV measurements or body composition estimates were used to assess within-laboratory precision (repeatability), as standard deviation (SD) and coefficient of variation; the differences between measurements reproduced at each laboratory were used to determine between-laboratory precision (reproducibility), as bias and 95% limits of agreement (from SD of the differences between laboratories). RESULTS: The extent of within-laboratory methodological precision for BV (uncorrected and actual) was variable according to subject, sample group and laboratory conditions (range of SD, 0.04-0.13 l), and was mostly due to within-individual biological variability (typically 78-99%) rather than to technical imprecision. There was a significant (P<0.05) bias between laboratories for the 10 repeats on the two independent subjects (up to 0.29 l). Although no significant bias (P=0.077) was evident for the sample group of 30 volunteers (-0.05 l), the 95% limits of agreement were considerable (-0.68 to 0.58 l). The effects of this variability in BV on body composition were relatively greater: for example, within-laboratory precision (SD) for body fat as % BWt was between 0.56 and 1.34% depending on the subject and laboratory; the bias (-0.59%) was not significant between laboratories, but there were large 95% limits of agreement (-3.67 to 2.50%). CONCLUSION: Within-laboratory precision for each BOD POD instrument was reasonably good, but was variable according to the prevailing conditions. Although the bias between the two instruments was not significant for the BV measurements, implying that they can be used interchangeably for groups of similar subjects, the relatively large 95% limits of agreement indicate that greater consideration may be needed for assessing individuals with different ADP instruments. Therefore, use of a single ADP instrument is apparently preferable when assessing individuals on a longitudinal basis.     

Urinary tract pathology in Schistosoma haematobium infected rural Nigerians

Parasitological investigation assessing the ova of Schistosoma haematobium in the urine of 138 volunteers in Ihieve-Ogben, Edo State, Nigeria revealed 43 positive results (31.2%). Children had a higher prevalence of urinary schistosomiasis 30 (41.1%) than their adult counterparts 13 (20.0%) and this difference was statistically significant (t = 8.89, p > 0.01). More volunteers had light intensity of infection 27 (19.6%) than heavy infection 16 (11.6%) and this difference was statistically significant (chi2 = 22.90, p>0.05). Ultrasonographic investigations carried out on these 43 S. haematobium infected volunteers revealed ten pathological conditions, including abnormal wall thickness 24 (55.8%), abnormal shape 30 (69.8%), irregular bladder wall 12 (27.9%), masses 10 (23.3%), pseudopolyps 2 (4.7%), echogenic particles 30 (69.8%), residual volume 12 (27.9%), calcifications 24 (55.8%), hydroureter 10 (23.3%) and hydronephrosis 8 (18.6%) when compared to control subjects which lacked bladder and kidney abnormalities. These pathological conditions were slightly more common in the volunteers with heavy infection than those with light infection, but this difference was not statistically significant (t = -2.19, p < 0.02). More pathological conditions were found in children than in adults; this finding was statistically significant (t = 3.23, p > 0.03). Hydronephrosis and hydroureter were not found in the volunteers with light intensity of infection.     

The gastrointestinal tolerability of the LOX/COX inhibitor, licofelone, is similar to placebo and superior to naproxen therapy in healthy volunteers: results from a randomized, controlled trial

OBJECTIVES: Concerns exist over the safety of conventional nonsteroidal antiinflammatory drugs (NSAIDs) and selective cyclooxygenase (COX)-2 inhibitors. In experimental models, licofelone, a competitive inhibitor of 5-lipoxygenase (5-LOX) and COX-1/-2, has been shown to have good gastrointestinal and general tolerability and analgesic and antiinflammatory properties. The aim of the present endoscopy trial was to investigate the gastroduodenal tolerability of licofelone compared to placebo and naproxen in healthy volunteers. METHODS: In this randomized, parallel-group trial, healthy volunteers received licofelone 200 mg b.i.d. (n = 30), licofelone 400 mg b.i.d. (n = 30), naproxen 500 mg b.i.d. (n = 30), or placebo (n = 31). Tolerability was assessed by gastro/duodenoscopy following 4 wk of treatment. Laboratory parameters and the incidence of ulcers and adverse events were recorded. RESULTS: Ulcers were observed in 20% of the naproxen-treated volunteers, compared with 0% of those receiving licofelone 200 mg, licofelone 400 mg, and placebo (p= 0.024). Posttreatment mean gastric Lanza scores were similar for volunteers who received placebo or either dose of licofelone, while Lanza scores were significantly worse following naproxen therapy (p < 0.00001). The gastric mucosa was normal in 93%, 89%, and 90% of volunteers who received licofelone 200 mg, licofelone 400 mg, or placebo, respectively, compared with 37% of volunteers receiving naproxen. The incidence of adverse events did not differ significantly between licofelone 200 mg or naproxen therapy. No clinically relevant changes in laboratory parameters were observed with licofelone or naproxen therapy. CONCLUSIONS: The results from this trial indicate that licofelone has a potential gastrointestinal safety advantage over conventional NSAID therapy, as licofelone was associated with significantly superior gastric tolerability and a lower incidence of ulcers compared with naproxen in healthy volunteers. Further trials will be required to investigate the safety and efficacy of licofelone in the treatment of diseases such as osteoarthritis.     

Doppler echocardiographic evaluation of valve regurgitation in healthy volunteers.

OBJECTIVE--To study the prevalence and the characteristics of physiological valve regurgitation. DESIGN--Pulsed wave Doppler echocardiography, continuous wave Doppler echocardiography and Doppler colour flow mapping were performed prospectively in healthy volunteers. SETTING--Echocardiography laboratory in a city hospital. PATIENTS--32 consecutive healthy volunteers (age 21-49 years, mean age 29.4). MAIN OUTCOME MEASURES--Identification of regurgitation with colour Doppler flow mapping and measurement of the jet area, jet length, and maximal velocity of the regurgitation. RESULTS--Regurgitation was recorded at the pulmonary (100%), tricuspid (100%), mitral (56%), and aortic valves (6%). The velocity of pulmonary and tricuspid regurgitation was similar to that predicted from the pressure gradient calculated from the Bernoulli equation. The jet area and jet length were generally small. CONCLUSION--Trivial regurgitation from the pulmonary, tricuspid, and mitral valves is common in healthy people. It is important to take such regurgitation into account when valve disease is diagnosed.     

Rapid oral hydration results in hydronephrosis as demonstrated by bedside ultrasound.

STUDY OBJECTIVE: To determine whether vigorous oral hydration (20 mL/kg) causes hydronephrosis as determined by bedside ultrasound. METHODS: We conducted a prospective laboratory trial in 35 healthy volunteers weighing less than 90 kg and between the ages of 18 and 50 years. The right kidney of the volunteers was scanned by emergency physicians at time 0 both before and after voiding, and the volunteers then drank 20 mL/kg of bottled water. The kidney was scanned in the transverse and sagittal planes both before and after voiding at 60 and 90 minutes after completion of the water load. The scans were interpreted by a physician trained and credentialed in emergency ultrasound, blinded to the volunteers' identity, the time of the scan, and the volume of urine voided by the subject. Images were rated as to the degree of hydronephrosis according to literature-established criteria, as follows: grade 0=no hydronephrosis, grade 1=mild, grade 2=moderate, and grade 3=severe hydronephrosis. RESULTS: Hydronephrosis was present in 3 (8.6%) of the 35 subjects at time 0 (prehydration), 24 (68.6%) at 60 minutes, and 20 (57.1%) at 90 minutes. Overall, hydronephrosis occurred at least once in 28 (80%) of the 35 subjects after oral hydration compared with 3 (8.6%) of the 35 subjects before hydration. Hydronephrosis was found to be significantly related to forced hydration for all posthydration times (60 minutes, 90 minutes, and 60+90 minutes combined) versus prehydration time 0 (P <.001). CONCLUSION: Without prior fluid intake, even mild degrees of hydronephrosis were relatively uncommon, and seen in only 8.6% of study patients. In the presence of vigorous oral hydration, however, mild or moderate hydronephrosis is a frequent occurrence seen at least once in 80% of our study of healthy volunteers after hydration. Caution is warranted in this setting when interpreting mild or moderate hydronephrosis found on bedside ultrasound by emergency physicians.     

Repeated automatic versus ambulatory blood pressure measurement: the effects of age and sex in a normal ageing population

OBJECTIVES: To study blood pressure adaptation in relation to age and sex. In a subsample, laboratory blood pressure measurements were compared with ambulatory daytime blood pressure measurements to determine the degree of agreement between the two methods. The night-time blood pressure reduction was analysed as a function of blood pressure status, age and sex. DESIGN: A cross-sectional study in 469 healthy volunteers, aged 23-82 years, stratified for age, sex and educational level. METHODS: Laboratory blood pressure was measured automatically (Dinamap 8100) five times during a 20 min recording session. Cardiovascular events in the medical history were identified in order to treat the cardiovascular event-free group separately in subsequent analyses. Within 3 weeks after laboratory blood pressure measurement, ambulatory blood pressure was measured for 24 h in 135 volunteers from the main study. RESULTS: Both diastolic and systolic blood pressure varied markedly in a single measurement session as a function of age, independent of mean pressure level. After 15 min no further blood pressure decrease was observed. On the basis of the average of the final two blood pressure measurements, 18.8% of the subjects were in the hypertensive range (WHO/ISH guidelines). Ambulatory blood pressure measurements were in accord with earlier findings and correlated 0.74 and 0.73 with laboratory diastolic and systolic blood pressure, respectively, but weighted kappa values indicated only moderate agreement (0.42 and 0.51). Women showed a more profound reduction in cnight-time blood pressure than did men. CONCLUSIONS: There is a substantial change in blood pressure during a single measurement session which is greater in older age groups. The moderate agreement between the two methods of blood pressure measurement supports the notion that blood pressure measured in a single session has limited generalizability to average daytime levels in a population sample.     

The effect of age on lower urinary tract function: a study in women

OBJECTIVES: To identify age-associated changes in female lower urinary tract function across a wide age spectrum, controlling for detrusor overactivity (DO). DESIGN: Secondary analysis of a cross-sectional study of DO and aging. Eligible volunteers were stratified by age group and presence of DO. SETTING: Community-based volunteers, evaluated in research laboratory. PARTICIPANTS: Eighty-five ambulatory, nondemented, community-dwelling female volunteers, with and without bladder symptoms suggestive of DO, recruited by advertising, mean age 54 (range 22-90); 75% Caucasian, 21% African American. MEASUREMENTS: Comprehensive assessment included bladder diary, uroflowmetry, and detailed videourodynamics. Predefined urodynamic and diary variables were examined for association with age and DO. Mean values of these variables were calculated for subgroups aged 20 to 39, 40 to 59, and 60 and older (14 subjects > or =70). RESULTS: Maximum urethral closure pressure, detrusor contraction strength, and urine flow rate declined significantly with age (P<.001, P<.001, P=.006, respectively), regardless of whether DO was present. Most elderly individuals continued to empty their bladder almost completely, with normal voiding frequency. Mean number of nocturnal voids was less than one in all age groups. Bladder capacity did not decrease with age (mean 522 mL in oldest group) but was smaller in subjects with DO. Bladder sensation diminished significantly with age (P<.001) but was stronger in subjects with DO. CONCLUSION: Female bladder and urethral function appear to deteriorate throughout adult life, whether DO is present or not. Specifically, detrusor contractility, bladder sensation, and urethral pressure decline. The common belief that bladder capacity shrinks with age may be related to DO rather than to aging itself.     

Phase II safety and immunogenicity study of live chikungunya virus vaccine TSI-GSD-218

We conducted a phase II, randomized, double-blind, placebo-controlled, safety and immunogenicity study of a serially passaged, plaque-purified live chikungunya (CHIK) vaccine in 73 healthy adult volunteers. Fifty-nine volunteers were immunized one time subcutaneously with the CHIK vaccine and 14 were immunized with placebo (tissue culture fluid). Vaccinees were clinically evaluated intensively for one month, and had repeated blood draws for serological assays (50% plaque-reduction neutralization test) for one year. Except for transient arthralgia in five CHIK vaccinees, the number and severity of local and systemic reactions and abnormal laboratory tests after immunization were similar in CHIK vaccinees and placebo recipients. Fifty-seven (98%) of 58 evaluable CHIK vaccinees developed CHIK neutralizing antibody by day 28, and 85% of vaccinees remained seropositive at one year after immunization. No placebo recipients seroconverted. This promising live vaccine was safe, produced well-tolerated side effects, and was highly immunogenic.     

Circadian abnormalities in older adults

This study examined the circadian phase adjustment of symptomatic elders ages 60-79 years in comparison with that of young, healthy adults ages 20-40 years. Seventy-two elders with complaints of insomnia or depression, and 30 young, healthy adults were assessed for 5-7 days at home. Sleep and illumination were recorded with Actillume wrist monitors and sleep diaries. Urine was collected over two 24-hr periods and assayed for 6-sulphatoxymelatonin (6-smt). The volunteers were then observed continuously for 5 nights and 4 days in the laboratory. In the laboratory, sleep periods were fixed at 8 hr with polysomnographic assessment of sleep, apnea-hypopnea, and nocturnal myoclonus. Circadian dispersion, defined as the mean variation of 6-smt acrophase from the median age-specific acrophase, was significantly greater in the older vs. young adults. Likewise, circadian malsynchronization, defined as the absolute number of hours (advance or delay) between the 6-smt acrophase and the middle of the sleep period, was significantly greater in the older vs. young volunteers. For the older volunteers, multiple regressions were calculated associating sleep with potential correlates of sleep disturbance. Nocturnal myoclonus and circadian malsynchronization were more strongly associated with sleep impairment than other factors (e.g., sleep apnea, depression). These observations suggest that circadian malsynchronization might be a common and significant cause of disturbed sleep among adults over age 60.     

Prevalence ofCampylobacter pylori and association with antral mucosal histology in subjects with and without upper gastrointestinal symptoms

To determine the incidence and significance of Campylobacter pylori in patients undergoing routine endoscopic evaluation at this hospital, biopsies of the antrum were obtained from 132 patients and from 15 asymptomatic volunteers. Specimens were cultured and silver stained for the presence of C. pylori and were examined histologically. C. pylori was detected in 67 (51%) patients and two (13%) volunteers (P = 0.006). In patients, C. pylori was found significantly more often when the mucosa was inflamed (67%) than when the mucosa was normal (13%), and both volunteers with C. pylori had chronic gastritis on histological examination. When compared to the volunteers, patients with upper gastrointestinal symptoms had a significantly increased prevalence of antral inflammation, even if the endoscopic examination was normal. C. pylori is infrequently found in young asymptomatic adults but is found in both asymptomatic volunteers and patients in association with all forms of histological antral gastritis which is prevalent in patients with both normal endoscopic findings and peptic ulcer disease.     

Laboratory reference values for healthy adults from southern Tanzania

Objectives To define and discuss reference ranges for commonly determined laboratory parameters in healthy adults from southern Tanzania. Methods A population‐based sample of adult volunteers from Mbeya, Tanzania, who were not HIV positive or showing signs and symptoms of other diseases, participated in this study. We enrolled 145 women and 156 men between 19 and 48 years of age to determine clinical chemistry (CC), haematology and lymphocyte immunophenotyping (LIP) parameters using standard laboratory methods. Medians and nonparametric 95% reference ranges for each parameter were determined and compared with reference ranges from the USA, Europe and from other African countries. Results Agreement with ranges from developed countries was poor: for CC values the average concordance was 80.9% and 86.7% with values from two developed countries. Haematology ranges from the USA classified 86.3% of values correctly, whereas ranges from three different sub‐Saharan Africa (SSA) sites classified between 82.5% and 94.5% of values correctly. The agreement of LIP reference ranges was 87.5% with values determined in Germany but between 91.7% and 95.8% compared with values determined at other sites in SSA. Conclusion Clinical reference ranges determined in developed countries are inadequate for use in SSA. Laboratories in this region should either define their own or use values determined under similar conditions. The ranges reported here are more appropriate for use in SSA than ranges determined in developed countries.