Biomedical subjects

D C Hale

Publications and source records attributed to D C Hale.

14 recordsLinked to original sources

PubMed1996

Use of a single slide trichrome-stained concentrate for the detection of intestinal parasites. Stained concentration procedure for ova and parasites.

The detection and identification of intestinal parasites was studied using a single slide of a trichrome-stained concentrate made from a cupric-polyvinyl alcohol (PVA)-preserved specimen. When saline was used in place of formalin in the concentration procedure, it was possible to adequately stain the concentrate with a modified-trichrome stain. This was compared to a more traditional two-slide ova and parasite (O&P) procedure. Of the 1,000 specimens evaluated, a total of 261 parasites were detected using the single slide, modified trichrome-stained concentrate compared to 249 from the formalin/Hemo-De wet mount and 226 from the unconcentrated trichrome stain. The detection rate of the single slide method was comparable to the combined detection rate of the two-slide method. The saline/Hemo-De concentration procedure has the advantage of using nontoxic saline in place of formaldehyde. This new method is more cost-effective because it requires the processing and evaluation of only one slide.

Animals↗

PubMed1994

Laboratory evaluation of urinary tract infections in an ambulatory clinic.

A 4-month evaluation of ambulatory patients with a suspicion of a urinary tract infection was performed. Specific objectives included assessment of five urinary screening methods, reevaluation of the necessity of the phenylethyl alcohol plate (PEA), and cost-effectiveness of screening for low colony count bacteriuria. Urine samples were collected as midstream, clean-caught specimens. A total of 142 samples, 87 from 79 symptomatic patients and 55 negative controls, were evaluated. All urine specimens were cultured using a 0.01 mL loop and a 0.001 mL loop onto Columbia sheep blood agar, MacConkey agar, and PEA agar. Twenty-four specimens (17%) were sterile, 64 (45%) were contaminated, and 54 (38%) were infected. Five urine screening methods were performed. These tests and their associated sensitivity and specificity are as follows. The Chemstrip 9 (Behring, Inc., Somerville, NJ) for leukocyte esterase and nitrate, 67%, 98%; microscopic analysis on spun urine, 79%, 93%; methylene blue stain for pyuria, 60%, 99%; Gram stain for pyuria, 45%, 93%; Gram stain for bacteriuria, 65%, 75%; and the URISCREEN (Analytab Products, Plainview, NY), 92%, 89%. Inclusion of a PEA plate for isolation of gram-positive organisms provided no additional information. Routine culture of urine samples at 10(-2) mL increased the contamination rate by 19%.

Ambulatory Care↗

PubMed1988

Evaluation of laboratory tests used in screening ambulatory patients.

Multiple other tests have been suggested for screening healthy patients. Hopefully, the above illustrations give a perspective with regards to the incidence of disease versus other causes that would lead to abnormal test results. The most frequent cause of an abnormal test result is physiologic variation, laboratory variation, or both. Even in laboratories with excellent quality assurance programs, the results falling outside the reference ranges most likely indicate physiologic variation, laboratory variation, or both. The physician will obtain more meaningful data from the laboratory when testing is ordered to confirm diagnostic suspicions that were raised during the history and physical examination of the patient. When a physician receives abnormal test results that were ordered as screening tests without any diagnostic suspicion, a search should be made for signs and symptoms that would correlate with that abnormal test. In the absence of any evidence that would indicate underlying disease, it would usually be unnecessary to pursue follow-up testing.

Blood Gas Analysis↗

PubMed1986

In vitro inactivation of aminoglycosides by apalcillin.

Apalcillin, at concentrations of 75, 150, 300, and 600 micrograms/ml, was combined in vitro with amikacin, gentamicin, netilmicin, or tobramycin. Incubation at 37 degrees C resulted in an apalcillin concentration-dependent and time-dependent decrease of aminoglycoside activity of up to 60%. Amikacin was the most stable and tobramycin was the least stable aminoglycoside under the conditions tested.

Amikacin↗

PubMed1983

Clinical evaluation of a lysis-centrifugation technique for the detection of septicemia.

A commercially available lysis-centrifugation blood culture system was compared with a two-bottle broth-culture system employing 100 mL of broth and 10 mL of blood per bottle to analyze 1,913 blood specimens. Of 154 clinically significant isolates, 89% were detected by the lysis-centrifugation technique, and 73% were detected by the broth-culture method. Twenty-seven percent of the organisms were detected only by the lysis-centrifugation technique, and 11% were detected only by the broth system. Fifteen polymicrobial cultures were encountered; the lysis-centrifugation technique detected 93% of the organisms in these cultures, while the broth-culture method detected only 20%. Isolated colonies of clinically important organisms were available 30 hours earlier with the lysis-centrifugation technique. These results suggest that the lysis-centrifugation technique may provide a substantial improvement over conventional methods for blood cultures.

Adult↗

PubMed1982

An evaluation of the practicality of the spot-indole test for the identification of Escherichia coli in the clinical microbiology laboratory.

Colony morphology and the spot-indole test were evaluated to assess the practicality of the rapid identification of Escherichia coli isolates directly from primary isolation plates. One hundred ninety-one lactose-fermenting, gram-negative bacilli were identified by standard testing procedures (either API-20E, Micro-ID, or a 5-test biochemical battery). These isolates also were tested with the spot-indole test, using either a 1% or 5% p-dimethylaminobenzaldehyde or 1% p-dimethylaminocinnamaldehyde reagent. Of the total 191 E. coli isolated, 128 (67.0%) were single-colony types on the primary plates, and 112 (58.6%) met the morphologic criteria and were positive and spot-indole testing. Of these 112, 111 (99.1%) were identified accurately as E. coli by the morphologic criteria/spot-indole approach. This method can be recommended as a practical diagnostic aid in the clinical microbiology laboratory as it allows significant cost and time savings for the majority of the most frequently isolated gram-negative bacilli.

Escherichia coli↗

PubMed1981

Evaluation of urine culture screening by light-scatter photometry.

Urine screening for bacteriuria by light-scatter photometry (Autobac) was evaluated for accuracy and compared with a colony count by the calibrated loop method. Incubation time, inoculum size, precision, and interference of particulate matter were evaluated in an effort to standardize the screening procedure. Results showed that urines could be accurately screened for Enterobacteriaceae by inoculating a single Autobac cuvette chamber with 0.1 or 0.2 ml of urine and determining the voltage change after four hours. A change of greater than or equal to 0.2 units indicates significant bacteriuria. Decreased accuracy was noted for urines having greater than 10(5) cfu/ml of Pseudomonas species or gram-positive cocci, possibly because these organisms grow more slowly.

Bacteriuria↗

PubMed1981

Rapid screening for bacteriuria by light scatter photometry (Autobac): a collaborative study.

A total of 2,720 urine specimens from three laboratories were evaluated by Autobac (Pfizer Diagnostics) and were compared with simultaneous colony counts for evidence of bacteriuria. Of 599 specimens with a colony count of greater than or equal to 10(5) colony-forming units per ml, 93.8% were detected within 6 h. This detection rate increased to 97% of 447 positive urine specimens when only specimens from patients not on antimicrobials were evaluated. The majority (77.9%) of positive specimens were detected as early as 3 h. Those specimens with greater than or equal to 10(5) colony-forming units per ml, which were negative by Autobac at 6 h, included organisms which are frequently considered to be contaminants (diphtheroids, lactobacilli, alpha and gamma streptococci, yeasts, and Staphylococcus epidermidis), or were from patients who were being treated with antimicrobial agents. Of 2,121 urine specimens with colony counts of less than 10(5), 98.1% were correctly determined to be negative by Autobac at 3 h. This percentage decreased to 86.0 at 6 h. The majority of these false-positive specimens were those with colony counts of 10(4) to 10(5) colony-forming units per ml. There appeared to be no major difference in results from the three laboratories or among the four lots of broth used in this study.

Anti-Bacterial Agents↗

PubMed1981

Rapid identification by the Micro-ID system of Enterobacteriaceae detected by urine screening.

Previous studies have demonstrated that organisms detected by urine screening can be processed for rapid identification and antimicrobial susceptibility testing directly from urine or urine screening broth. In the present study, an improved method for processing such specimens was evaluated. Organisms were harvested by centrifugation from positive urine screening broth, and inocula were prepared for rapid identification by the Micro-ID system and rapid susceptibility testing by the Autobac system. Nearly 2,500 urine specimens were analyzed by urine screening, and 206 specimens had significant growth of gram-negative, oxidase-negative bacilli. These organisms, prepared by the centrifugation procedure, were identified and tested for susceptibility to antimicrobial agents. For comparison, identifications by the Micro-ID system and antimicrobial susceptibility tests by the Autobac system were performed on the same organisms the next day with inocula prepared from colonies growing from standard urine cultures. The results demonstrated that 95% of the organisms were correctly identified by this procedure, and susceptibility testing by the rapid method gave results in 94% agreement with the standard method. These results demonstrate that organisms detected by urine screening can be accurately identified and tested for antimicrobial susceptibility after centrifugation from urine screening broth. This system provides a practical procedure or same-day reporting of urine culture results.

Anti-Bacterial Agents↗

PubMed1981

Toxic shock syndrome.

Eight cases of toxic shock syndrome, confirmed by Center for Disease Control criteria, involved women who were menstruating and were tampon users. Each patient had severe febrile illness with rash, associated hypotension, renal and liver function abnormalities, pharyngitis and vaginitis. An examination of the literature indicates that cases that were reported as adult Kawasaki disease may actually have been toxic shock syndrome.

Adolescent↗

PubMed1980

In-vitro inactivation of aminoglycoside antibiotics by piperacillin and carbenicillin.

Clinical microbiology laboratory experiences wherein aminoglycoside serum assay results appeared inconsistent with the amount of the compound given when administered in combination with a semisynthetic penicillin led us to compare the interaction of three currently available aminoglycoside antibiotics with carbenicillin, as a representative semisynthetic penicillin given in large doses, and with piperacillin, a new broad-spectrum semisynthetic penicillin. Amikacin, gentamicin, and tobramycin were incubated in serum in vitro with various concentrations of carbenicillin and piperacillin. In the presence of very high concentrations of the two penicillins, tobramycin was the most rapidly inactivated aminoglycoside, gentamicin was next, and amikacin was only slightly inactivated. With low concentrations of the two penicillins, the rates of aminoglycoside inactivation were negligible. Carbenicillin, in high concentration, inactivated the aminoglycosides more rapidly than piperacillin. In patients experiencing renal failure, the maintenance of moderate serum levels of carbenicillin and piperacillin may be important in attempting to maintain adequate aminoglycoside serum levels.

Amikacin↗

PubMed1980

Rapid semiautomated screening and processing of urine specimens.

A rapid urine culture procedure was evaluated in which positive urines were detected by using light-scatter photometry (Autobac). Specimens were analyzed at 3, 5, and 6 h. Specimens detected as positive at 3 h were then further evaluated by a direct 3-h susceptibility procedure (Autobac) and by a 4-h identification procedure (Micro-ID). Of 949 specimens, 175 had >10(5) colony-forming units per ml by colony count. Of these latter specimens, 75.4% had been detected by 3 h, and 95.4% were detected by 6 h. Of specimens positive by Autobac at 3 h, 96% (95.7%) had >10(5) colony-forming units per ml. If pure by Gram stain, those positive specimens were inoculated to direct susceptibility and identification systems. When direct Autobac susceptibilities were compared with the standard Autobac method done from the plate the following day, discrepancy rates were 1.3% very major, 2.1% major, and 7.4% total. The direct identifications were 94% (94.2%) correct when using the Micro-ID manual and a collection of octal patterns unique to this system, in which urine/broth culture inoculum was employed instead of the usual organism colony suspension. Those urine specimens negative after screening at 3 h were evaluated at 5 and 6 h, and an additional 126 specimens were detected as positive. These were then processed by routine plate inoculation, due to the limitations of the work day. By 6 h, 95.4% of specimens with >10(5) colony-forming units per ml were detected. The 4.6% false-negative results consisted of patients on antibiotics, or slowly growing bacteria suspected of being distal urethral contaminants. Thus, 83.5% of the urine cultures received by 9:00 a.m. (10.6% 3-h positives and 72.9% negative at 6 h) could be evaluated and reported within one 8-h work day.

Anti-Bacterial Agents↗

PubMedDate not supplied

The nature of an infectious disease practice in a community hospital.

Populations of patients in community and university-affiliated teaching hospitals differ, and therefore, problems encountered by infectious disease specialists in these two types of hospitals also differ. However, most infectious disease specialists are trained only in university hospitals. In order to characterize the nature of an infectious disease practice in a community hospital, the authors report data for the patients seen during a period of three years (July 1978-June 1981). Most of the 1,238 cases were referred by other physicians. General practitioners referred 35% of the cases, whereas internists, orthopedists, and surgeons referred 20%, 16%, and 10% respectively. Skin and wound infections accounted for the largest percentage of referrals (16%). Fever accounted for 9%, abdominal problems for 6%, and respiratory infections for 6%. Other problems referred to the infectious disease service included infections of the central nervous system, urinary tract infections, osteomyelitis, and arthritis.

Abdomen↗

PubMedDate not supplied

Pediatric travel consultation in an integrated clinic.

BACKGROUND: In May 1997, a pediatric travel service was created within a larger integrated University-County Health Department international travel clinic. The purpose of the service was to further enhance the travel advice and care provided to children and their parents or guardians. The current study was designed to describe the care of children in this setting and to compare the care of children seen in the Pediatric Travel Service with that of children seen by other providers. METHODS: All pediatric patients (defined as individuals < or = 18 years of age) receiving care in the travel clinic were considered candidates for inclusion in the analysis. Patients seen by the Pediatric Travel Service were compared to those seen by other staff members in the travel clinic (referred to as Regular Clinic). The following information was noted: basic demographic data, medical history including allergies, prior immunization records, intended place and duration of travel, and immunizations and medications prescribed at the time of visit. Travel advice covering water and food precautions, preventive measures against insect bites, injury prevention, malaria prevention, prevention of parasitic infections, and environmental-related problems was provided to all patients in both groups when necessary. RESULTS: Between May 1997 and December 1999, 287 pediatric age individuals were given pretravel care by the Pediatric Travel Service (median age, 6 years; range, 1 month-18 years). During the same time period, 722 pediatric age travelers (median age, 14 years; range, 8 months-18 years) were evaluated in the Regular Clinic by other staff members. Travel destinations most commonly traveled by both groups in descending order were: Africa, Central America and Mexico, South America, and Southeast Asia. When compared to travelers seen in the Regular Clinic, individuals in the Pediatric Travel Service group were more likely to travel for humanitarian work, and for parental work relocation. Persons in the Regular Clinic were more likely to travel to Mexico and Central America. They were also more likely to travel on vacation and for missionary work or study. Hepatitis B and tetanus-diphtheria booster vaccinations were given more frequently to travelers seen in the Regular Clinic. Also, ciprofloxacin and antimotility agents were more commonly prescribed in this group. No differences were noted in the duration of travel or in the time interval between clinic visit and departure. CONCLUSION: While general travel advice was considered to be similar in both clinic groups, some differences were observed in the frequency of administration of certain vaccines and prescriptions of medications. These differences were likely due to a difference in age in the two study groups. The high volume and success of the clinic suggest that integrated pediatric and adult travel services in a coordinated setting can be effective.

Adolescent↗