Clinical Laboratory Workers Research Articles

Effect of Plate Size and Location of Disc on Zone Diameter in the Disc Antimicrobial Susceptibility Test

An established standard antimicrobial disc susceptibility test recommends the use of a 150-mm petri dish. Many workers substitute 100-mm plates and use various types of mechanical dispensers. A comparison of zone diameters was made by testing Staphylococcus aureus and Escherichia coli against penicillin and chloramphenicol with the use of these different sized plates and dispensers. Zone diameters were consistently smaller at the edges of plates than in the center (0.4 to 1.2 mm). Significant small differences of up to 1.2 mm or no differences were observed when the mean diameters from these various plates were compared. All of the zone diameter measurements fell within accepted values for analytical variability in this procedure. There is no evidence that any individual combination of plates, dispensers, or disc locations provides greater precision in zone diameter measurement. More difficulty was encountered in measuring zones at the periphery of small plates. This suggests that busy clinical laboratory workers might not produce work of comparable quality with the smaller plates.

Manual of Clinical Microbiology.

It is a pleasure to review a book of such true excellence. Blair, Lennette, and Truant are to be congratulated for a superb job of assembling material covering the identification and isolation of bacteria, fungi, parasites, and viruses in a single volume. Usually manuals of this type are of interest only to the clinical laboratory worker. In this instance I feel this volume is a must for any internist whose subspecialty interest is infectious diseases. Large medical centers have microbiology laboratories staffed by well-trained individuals whose primary interest is clinical microbiology. But some hospital laboratories may not have kept abreast of the great progress that has occurred in the last decade. Improvements in transportation of specimens, isolation of Neisseria gonorrheae and N meningitidis , and identification of members of the family Enterobacteriaceae are examples. Consultation with this manual will allow the internist to review his hospital's microbiological methods with authority. One

Recent Advances in Clinical Pathology.

The four editions in this series of Recent Advances have spanned 17 years. These have been years in which Clinical Pathology, along with other specialties of medicine, has undergone a great deal of change. The basic medical sciences have produced an enormous body of information with varying degrees of relevance to the practice of clinical medicine. The clinical pathologist is faced with the task of selecting and correlating bits of this knowledge from dozens of scientific disciplines and converting them, through the medium of laboratory technology, into useful roles in the diagnosis and treatment of disease. The transition from scientific discovery to practical utility has proved exceedingly tedious and time consuming for clinical laboratory workers. We see this reflected in the number of very old methods that continue to be used in day-to-day laboratory practice. Frustrations of the clinical pathologist are expressed many times throughout this volume in such statements

Laboratory Diagnosis of Protozoan Diseases

The appearance of this authoritative manual fills a recognized need for all clinical laboratory workers and internists. The make-up, typography, binding and size are attractive, and highly convenient and efficient. The colored plates and illustrations are definite additions to its practical value and usefulness. No clinical or military laboratory can possibly afford not to have it available.The section on amebiasis occupies 114 of the 328 pages of text. This section is unusually well done, even for the author. The reader notes with pleasure the extremely systematic, practical and condensed discussions on ameba-culture and complement fixation. In this, as in all sections, the author's authoritative and direct critical evaluation of methods is excellent. It is possible that the clinician will value sigmoidoscopy in diagnosis more highly than does the author. Also it seems to me that stained and especially hematoxylin-stained preparations do not receive as much diagnostic credit as they deserve.

Gonorrheal infection of the kidney pelvis: Report of four cases

The finding of gram-negative intracellular diplococci, morphologically gonococci, in a specimen from the kidney pelvis is the most important single factor in the diagnosis. Culture is too delicate a procedure to be expected routinely. Sometimes even formaldehyde or other agents used in sterilizing ureteral catheters may so affect the bacteria that no growth results. Contamination may overshadow and force the gonococci out of the picture. Culture of gonococci on Schwartz media from the urethral pus in an ordinary acute case of gonorrhea is often successful in the hands of the highest class of clinical laboratory worker, but one must be highly optimistic to expect a high percentage of positive cultures in cases of mixed infections. Case records in the literature fail to disclose any case of micrococcus catarrhalis infection that could well be mistaken for gonorrhea if the ordinary precautions and conscientious efforts, coupled with adequate experience in staining and examining smears of urethral pus, be exercised; while infection of the urinary tract by the meningococcus, unaccompanied by the clinical picture of meningitis, is such a remote possibility as to leave it out of consideration. Of the cases presented, two underwent operative procedure, one nephrectomy and the other nephrolithotomy. One is still under treatment. Diagnosis was established microscopically previous to operation. Considering the advanced cases which come to the urologist, it is not at all surprising that a goodly number of these kidney infections come to operation. Subjecting a patient with acute or subacute gonorrhea to ureteral catheterization is, generally speaking, contraindicated. However, in cases of long-standing gonorrhea with the second glass of urine of a two-glass test as cloudy as glass I, containing a large amount of albumin, and after the lower genitourinary tract is considered excluded from the standpoint of sufficient pathology to account for these findings, especially when accompanied by a feeling of tightness, dragging sensation or pain in either costovertebral angle, one should be led to seriously consider ureteral catheterization.