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Traditional genetic marker systems rarely fail to resolve paternity disputes when two or more men are accused, except when men are brothers. A sibling of the biologic father may not be excluded by these laboratory tests and sometimes yields calculated odds of paternity that are equal to or higher than the true male parent. Resolved two-brother cases were compared with resolved cases involving two unrelated men. In each case, the residual odds of paternity were determined for each man and the greater was divided by the lesser to produce a paternity fraction. The paternity fraction is a useful indicator of biologic parentage when it exceeds a value of 10 (log10 of-the-odds score greater than or equal to 1). Tests for alleles at highly heterozygous loci are indicated in initial laboratory evaluations of cases involving brothers. Human leukocyte antigen and variable number of tandem repeat polymorphisms appear suitable.

A newly discovered case of heteropaternal superfecundation (HS) is reported. Three HS cases were found in a parentage test database of 39,000 records. The frequency of HS among dizygotic twins whose parents were involved in paternity suits is 2.4%. Although the study population appears similar to the general population with respect to twinning data, inferences about the frequency of HS in other populations should be drawn with caution.

Parentage analysis has revealed a high probability that a man accused of paternity is the biological father of a male child. The child in this study, however, was the twin of a female child who could not have been fathered by the accused man. The mother of the children subsequently accused a second, unrelated man, who was excluded from paternity of the boy, but was very probably the biological father of the girl.

Gc allele frequencies were determined in Haitian immigrants, a group at high risk for AIDS. Gc2, an allele associated with disease resistance, is infrequent in this group; Gc1f is frequent.

Based on findings in 2 fluoride-toxic patients, it was suspected that hyperkalemia played a clinically important role in the etiology of sudden death from fluoride poisoning. Using fluoridated human erythrocytes as an in vitro model, it was confirmed that fluoride produced a marked potassium efflux from intact cells. Further, neither glucose and insulin in pharmacologic doses, nor various buffers could halt the efflux by shifting the potassium intracellularly. If these results can be extrapolated to the clinical situation, removal of potassium and fluoride via exchange resins or dialysis remains the only reasonable approach to this life threatening problem. Aside from sudden hyperkalemia and hypocalcemia, no serologic marker for fluoride toxicity has been identified. A high degree of clinical suspicion is therefore essential to the diagnosis.

Current methods for determining serum chloride concentration vary in specificity. Laboratory detection of bromide in serum is usually dependent on spuriously high chloride values. In the absence of historical information, the chemical identification of bromide in serum may be the only diagnostic sign of bromism. Bromide may be found in as many as 1% of sera obtained from inpatients of a general hospital. Ion-selective electrodes and some thiocyanate methods for chloride analysis can be highly sensitive to bromide (interference). Chloride electrodes are also sensitive to iodide.

Urine sediment of a hemizygous patient with Anderson-Fabry disease contained characteristic myelin bodies on ultrastructural examination. Such examination offers an alternative, noninvasive, relatively simple means of establishing early diagnosis.

Locally recurrent, poorly differentiated carcinoma of the prostate was associated with hypokalemic alkalosis, marked hypernatremia, diabetes mellitus of recent onset, and hyperosmolar syndrome. These findings, with mild hypertension, in the absence of clinical features of Cushing's syndrome, suggested an ectopic ACTH syndrome. Plasma ACTH and cortisol levels were markedly elevated, and failed to suppress in response to either low or high-dose dexamethazone administration. The patient's condition deteriorated rapidly. Autopsy findings included carcinoma extensively infiltrating the prostate with extension to the urinary bladder, and metastases confined to the pelvic nodes and soft tissues. The adrenal glands weighed 23 g and showed diffuse hyperplasia. Extract of the prostatic tumor was analyzed for ACTH and showed approximately 40 times normal plasma levels (or about 4,010 pg/g of tissue); ultrastructural features showed secretory granules consistent with ACTH content of the tumor cells. Such cells were positive when stained for ACTH by peroxidase-tagged immunochemical methods. The case fulfills all established criteria for relating excess corticosteroid production and nonpituitary tumors.

Six erythrocyte antigen systems and the HLA system were evaluated to establish their practical value in 500 cases of disputed paternity. The actual results were very close to predicted values. HLA testing is expected to detect 92% and red cell testing is expected to detect 67% of men falsely accused in paternity suits. The findings of this study show that HLA detected 94% and red cell testing detected 69% of 107 men falsely accused in 500 paternity cases. In order of sensitivity, Rh, MNSs, and ABO were the most useful erythrocyte marker systems. There were six out of 107 cases in which exclusions would have been undetected if red cell typing had not been performed. Five of the six cases involved "common" HLA haplotypes.

A filing system of cumulative patient record cards is described for use by large or active blood banks. Cards are retrieved for review of patient identification, past transfusion history, and legally necessary documentation of test results. Information on the cards is handwritten (as is required in most blood banks) only once, reducing transcription error. Card acquisition depends on an electromechanical delivery system, which is selectively activated by a programmed key-stroke sequence. Cards are filed and accessed randomly so that records cannot be lost. A backup system for delivery permits certainty of retrieval of records. The system contains 40,000 complete patient records on line, can easily be expanded, may be linked to off-line files or a computer, and is simple to operate.

Study of a large five-generation kindred from southern Maryland revealed that type III dentinogenesis imperfecta (DGI-III) and a localized form of juvenile periodontitis (JP) were both segregating as autosomal-dominant traits. Linkage analyses demonstrated that these were two distinct clinical entities, making this family the first documented instance of an autosomal-dominant form of JP. Since the locus for the more common form of dentinogenesis imperfecta (DGI-II) is on chromosome 4q [Ball et al, 1982], a linkage analysis of genetic and chromosomal markers on chromosome 4 was undertaken. The results suggested that the locus for the DGI-III subtype is located a similar distance from the Gc locus (theta = 0.12) as the distance previously observed between Gc and DGI-II loci (theta = 0.11) [Ball et al, 1982; Conneally et al, 1984]. Most likely the two DGI subtypes are determined by genes at closely linked loci, by allelic genes, or by the same gene with the variable expression in different families. In addition, close linkage between the Gc locus and that determining the autosomal-dominant form of JP was observed in this family (theta = 0.05). The known map of chromosome 4q and our analysis of the markers tested suggested the gene order to be 4cen----JP----Gc----DGI----MNS----qter with a large distance (at least 15 cM) between 4cen and JP.

The mechanism of sudden cardiac death following acute fluoride intoxication has been thought to result from profound hypocalcemia produced by the precipitation of calcium fluoride salts. In studies of a canine model, the onset of lethal ventricular arrhythmias was temporally more associated with an elevation of serum potassium than with a drop in serum calcium. Fluoride-induced hyperkalemia could not be prevented with glucose, insulin, or bicarbonate. In the erythrocytes, a five-minute exposure to 10 mM NaF caused a 50% increase in extracellular potassium concentrations after 12 hours compared to control erythrocyte suspensions (P less than .001). The total potassium efflux after 12 hours of incubation was linearly related to the log of fluoride contact time (r, 0.886; P less than .001). The treatment of fluoride-induced hyperkalemia may depend on removal of fluoride and potassium.

The relative frequency of Kell (K:1) antibodies in pregnant women and a series of cases of Kell hemolytic disease of newborns were evaluated to review the strategy of managing potential disease. Among reproductive-aged women, Kell antibodies are about 60% as frequent as Rho (D) antibodies, but Kell disease is only 3% as common as Rho hemolytic disease. The reason is related to frequent transfusion-alloimmunization by Kell antigen and the low frequency of the K:1 gene among fathers. Kell hemolysis is severe in about half of cases. Amniocentesis is indicated in only a few circumstances: previous child with erythroblastosis fetalis, significant increase in maternal Coombs titer, presence of Kell antigen in the father, and after comparison of the relative risks of hemolytic disease and amniocentesis in each patient. Screening for Kell antigen before transfusing premenopausal women would be a means of avoiding erythroblastosis, but the rarity of severe disease does not justify this approach.

A study was made of hr'(c) hemolytic disease to determine its natural history and to develop criteria for its management. Anti-c is 0.52 as frequent as anti-D(Rho) in gravid women. Seventy-four percent of infants born of c-alloimmunized women mated to c-positive men show serologic evidence of hemolytic disease of newborns. Up to 40% of affected infants require transfusion. There is evidence that ABO incompatibility between mother and fetus protects against alloimmunization. Although alloimmunization is frequently related to fetomaternal bleeding, severe hemolytic disease appears to be associated with previous maternal transfusion. Maternal antiglobulin titers of less than 1:16 are usually associated with mild disease or none at all. Women with higher titers, whose mates are hr'(c)-antigen positive, are candidates for amniotic fluid pigment analysis.

The exact pathways of urinary reflux into the renal veins were studied in four cases of clinical obstructive uropathy and in 50 normal human cadaver kidneys. In the four clinical cases Tamm-Horsfall uromucoprotein was used as a marker for location of urine. Routine light microscopy and indirect immunofluorescence for Tamm-Horsfall uromucoprotein using rabbit antiserum showed tubular backflow up to the glomerulus. Dilated tubules filled with Tamm-Horsfall uromucoprotein ruptured into thin walled veins, forming tubulovenous anastomoses with extrusion of their contents into veins. The uromucoprotein was present in interlobar and arcuate veins with superimposed thrombosis and thrombophlebitis. Injection studies using pigmented gelatin in 45 normal cadaver kidneys and pigmented vinylite with corrosion casts in five additional kidneys complemented the clinical studies. Two types of urovascular communication were produced: the less frequent direct pyelovenous communication between a rupturing fornix and an adjacent small vein, and the more common indirect pyelovenous communication in which a ruptured fornix produced a sinus extravasate, which extended along the perivenous spaces of interlobar and arcuate veins. This extravasate gained access into the veins at points of rupture where venous tributaries joined the major veins in the renal medulla. The clinical implications of these tubulovenous and pyelovenous pathways of urinary reflux include backflow of whole urine and continued nephronic function in obstructive uropathy, "reverse backflow" of blood and hematuria, and a direct access for infectious agents into the circulation. These channels provide anatomic correlates for radiologic findings of extravasates and some backflow patterns of contrast material in pyelograms of clinical obstructive uropathy. The possible immunologic consequences of refluxing Tamm-Horsfall uromucoprotein gaining access to tissues and circulation are speculative.

Immunogenetic study of alleged first-degree relatives was undertaken among 258 prospective United States immigrants from Haiti. Methods involved serotyping red cells for ABO, Rh, and MN antigens and typing leukocytes for HLA, A, B, and C locus antigens. Kinship was definitely excluded in a relatively low 4.2% of cases involving putative parents and children. Among cases involving alleged siblings, estimates of fraud appeared slightly higher, but the method is suspect because even in true sibships, there may be an absence of obligatory gene markers. Data suggests that some cases involved half-siblings rather than fraud. Of demonstrated exclusions of parent or child, HLA detected the lack of kinship in 87.4% versus 16.9% by red cell typing. However, there were cases in which exclusions were found by red cell methods alone; furthermore, red cell plus HLA typing allows for a calculation of probability of kinship that is analogous to calculations in paternity studies. Together, the red cell and leukocyte systems offer a prior probability of exclusion of parent-child relationships in 91.3%.

Blood specimens from white and black sample populations from Baltimore, Maryland, were analyzed for the four most forensically important, polymorphic red cell enzyme systems-phosphoglucomutase-1, esterase D, erythrocyte acid phosphatase and glyoxalase I. The distributions of the phenotypes for each marker in each racial group were in Hardy-Weinberg equilibrium. The population data were similar to previously reported data for Whites and Blacks from different geographical locations within the United States.

An extensive study was undertaken to compare five methods of blood smear preparation. Three mechanical devices for preparing blood smears were compared to the traditional coverslip and manual wedge methods. A series of five slides was prepared from each sample of blood. One hundred-cell leukocyte differential counts, red cell morphology, and platelet distribution were compared. Differential counts along the axis and margins of each slide failed to reveal any significant distribution difference by method. On the other hand, there were a significantly fewer neutrophils as well as higher lymphocyte counts on the two spinner preparations. Subsequent analysis suggested that spinner preparations create more smudge cells in smears of normal and granulocytic leukemia patients, and significantly fewer smudge cells in smears of lymphocytic leukemia patients. Both spinner methods produced significant increases in erythrocytic target cells, spherocytes, and cells with shifted pallor; and significantly fewer burr cells and ovalocytes, as compared to the reference methods. The mechanical wedge device was most similar to both reference methods. Of the two reference methods, the cumbersome coverslip preparation apparently offers no practical advantage over wedge methods.

The histologic and ultrastructural features of nephrogenic adenomas of the urinary bladder and urethra were studied in multiple specimens obtained from eight patients. Three of these were studied by indirect immunofluorescence for Tamm-Horsfall uromucoprotein. The lesions are uncommon benign metaplastic proliferations of urothelium, occurring most frequently in males as small cystic, papillary, or nodular masses and most often presenting with hematuria. Typically the metaplastic tubules resemble nephronic tubules. A florid atypical and pseudoinfiltrative proliferation of these tubules may led to an erroneous diagnosis of adenocarcinoma. Ultrastructural features of proximal convoluted tubules were identified in some of the tubules, but resemblance to specific segments of distal tubules was less certain. The ultrastructural features combined with the absence of Tamm-Horsfall protein in tubular lumina or cells suggest a mesonephric rather than metanephric homology. The lesions are appropriately treated by transurethral resection or fulguration, but persistent lesions were present in three patients up to 18 yeas after initial treatment.

A simple modification of an alpha-amylase (E.C. 3.2.1.1.) procedure, using blue starch substrate, permits quantitative results after three minutes of incubation. The procedure, performed on blank, control, and unknown speciemns, takes advantage of the heat stability of the enzyme and provides immediate and reliable data for acutely ill patients. The performance characteristics of the test on serum and urine are described. The method is distinctly advantageous in prividing rapid results for serum amylase, urine amylase, and amylase clearance in patients with suspected pancreatitis.

Two cases of tetracycline-associated fatty liver of pregnancy are reported. In one, the history was negative for antibiotic use, yet autopsy revealed typical gross and microscopic bone fluorescence of tetracycline. Tissue extraction and chemical analysis showed qualitative evidence of tetracycline, whereas quantitation revealed 60 microgram/gm of wet bone tissue. Findings in our cases and in those from the literature indicate that the association of tetracycline use and fatty liver of pregnancy is even more common than has been suggested.

We evaluated and inter-compared several newer methods for CO2 analysis--titrimetric (Van Slyke), automatic titrator, continuous-flow/indicator, and coupled-enzyme procedures--with respect to accuracy, precision, specificity interferences, and management criteria. All methods studied appeared to be clinically acceptable; but precision decreased (standard deviations increased) for the last two methods in above-normal ranges.

This study evaluates the usefulness of maternal serum concentrations of human placental lactogen in the management of high-risk pregnancies. The study was performed in a community hospital over a year's time and involved 250 gestations. The test detected only 11.4% of the pregnancies defined as high-risk by clinical criteria and none of the pregnancies in which the newborn was compromised. Serum human placental lactogen is an insensitive test in predicting the outcome of pregnancies in an obstetric population unless historical information regarding maternal disease is unavailable.

An unusual case of sudden, fulminant pneumococcemia and disseminated intravascular coagulation occurred in a woman who had had incidental splenectomy 8 months previously, at the time of gastrectomy for duodenal ulcer. Similar cases in which there is constant relationship of splenectomy, pneumococcal sepsis, and Waterhouse-Friderichsen syndrome have been documented. Other similarities which are notable are a tendency for the disease to occur in women, lack of a nidus of infection, and proliferation of diplococci to numbers great enough to be seen easily on the peripheral blood smear.

This chapter is an attempt to organize and summarize a diverse literature concerning Tamm-Horsfall uromucoprotein. Importance of examination of urine sediment for casts and diagnostic classification of casts have been discussed. Despite a lack of understanding of its biologic function, clinicopathologic study of T-HM has implicated it as a component of a variety of disease states. It binds a number of proteins, including those on surfaces of bacteria and viruses. It inactivates enzymes of those organisms, possibly by reacting with ionic cofactors, such as divalent metals. Ionic binding of monovalent cations (e.g., Na+) and repulsion of anions, such as Cl-, suggest a role for T-HM in renal salt and water balance. The combination of T-HM with ions, including H+, and other materials that enhance gel formation may indicate an ion-exchange function. Gel (cast) formation in the lower nephron, however, may produce obstruction, which, following calcification, infection, or inflammation, could go on to produce stones, increase scarring, and augment reflux nephropathy. Pathogenetic roles in autoimmunity and disorders of mucus metabolism have also been speculated on.

Maternal blood, amniotic fluid, and chorionic villus samples may be evaluated in the prenatal detection of neural tube defects, cytogenetic disorders, and inborn errors of metabolism. Laboratory tests for these abnormalities usually involve very specialized methods. They should be accompanied by equally rigorous clinical follow-up methods and expert counseling.

A new variant of blood group A [A(WAS)] was expressed in three generations of a Caucasian family: Phenotype included weak mixed field hemagglutination by anti-A reagents, secretion of H substance, and presence of anti-A1 in serum. The A(WAS) variant was inherited in a Mendelian fashion, dominant to O. A-transferase activity was absent from cells and saliva but was 0.2% of normal A1 transferase activity in serum, with a pH optimum of 6.0. Family members expressing A(WAS) also demonstrated partly deficient H type on cells (Hm). H-transferase activity in serum was normal for a weak A subgroup and showed typical Km and acceptor specificities. Linkage of H-modifier and ABO loci cannot be excluded.

Standard business inventory procedures can be cost effective when they are adapted to hospital laboratory inventory management in a 500-bed hospital. The investment in a central laboratory store-room and one additional employee yields financial benefits and indirect service benefits. The system requires consistent use of simple procedures throughout the laboratory, and can be coupled with improved strategies for purchasing supplies.

A search was conducted to find evidence of possible incestuous unions between the biologic parents of children involved in 2500 paternity cases. Suspicion was raised when either (1) a mother and her child possessed identical HLA phenotypes, or (2) the child appeared to be possibly homozygous for one maternal haplotype (i.e., one of the child's HLA haplotypes was a blank). These mother-child HLA-haplotype dualisms (MHDs) occurred in 5% of all cases. Frequency of exclusion of the accused men in cases demonstrating MHD, was compared with the remaining paternity cases. No significant difference was found in overall exclusion rates between MHD cases and controls when exclusion produced by HLA and red cell antigen systems were observed. However, there was a greater rate of exclusion in MHD cases when comparing exclusions produced by red cell antigen systems regardless of whether HLA tests excluded paternity (p less than 0.025). MHD cases involving teenaged mothers differed from control cases in frequency of exclusion of paternity only on the basis of red cell antigen phenotyping (p less than 0.005). The HLA system's usefulness in paternity testing is diminished when there is MHD; multiple, independently-inherited systems are relatively more useful in these circumstances. The search method detects only half of potential incest cases; proof of incest requires more extensive testing for homozygosity among other polymorphisms. Since calculations of likelihood of paternity are inappropriate in cases involving close consanguinity, detection and follow up studies are important. Data suggest that one-fifth of MHD cases may involve first degree consanguinity and that the incest rate among paternity cases may be as high as 2%.