Biomedical subjects

D P Snower

Publications and source records attributed to D P Snower.

4 recordsLinked to original sources

PubMed1991

Reevaluation of the periodic acid-Schiff stain in acute leukemia with immunophenotypic analyses.

To determine the sensitivity and specificity of the periodic acid-Schiff (PAS) stain in the diagnosis of acute leukemia in light of the finer characterization of this disorder now available through immunophenotyping, we examined the blasts from 51 patients with newly diagnosed acute leukemia by morphological, cytochemical, and immunophenotypic analyses. The 51 patients represented every new case of acute leukemia subjected to cytochemical stains and flow cytometry between July 1987 and February 1989. By cell-surface marker analysis, 29 exhibited lymphocytic lineage, while 21 were myelocytic. One was mixed lineage. The PAS positivity, defined by the presence of blocks or coarse granules in 5% or more of the blasts, was found in 15 of 29 lymphoblastic leukemias and in four of the myeloblastic leukemias. However, PAS-positive lymphoblastic leukemias were negative with the other cytochemical stains: myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase. The PAS-positive myeloblastic leukemias were positive with at least one other stain. Three cases of myeloblastic leukemia exhibited greater than 10% PAS-positive blasts, with all three being acute monoblastic leukemia. Thus, the sensitivity and specificity of the PAS stain alone for lymphoblastic leukemia was 52% (15 true positives of 29) and 81% (four false positives), respectively. The sensitivity of a cytochemical-staining combination of PAS positivity and myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase negativity in defining cases of lymphoblastic leukemia remained at 52%; however, the specificity of this combination for lymphoblastic leukemia was 100% (no false positives). Thus, a positive PAS stain, in combination with negative myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase stains, continues to have a diagnostic role in the distinction between lymphoblastic and myeloblastic leukemia, and greater immunologic sophistication serves to support this position.

Acute Disease↗

PubMed1989

Aeromonas hydrophila infection associated with the use of medicinal leeches.

The use of medicinal leeches (Hiruda medicinalis) is becoming more common after plastic surgery to control venous congestion of skin grafts. We describe a patient with Aeromonas hydrophila infection whose graft was treated with medicinal leeches. The infection required systemic antibiotic therapy. A. hydrophila is the predominant bacterial flora in the gut of the leech, where it plays an essential role for the animal in the digestion of blood. The potential for A. hydrophila wound infection, and appropriate antibiotic prophylaxis of the leech or patient, should be considered when medicinal leeches are used.

Aeromonas↗

PubMed1989

Ectopic pregnancy: duplex Doppler evaluation.

Of 398 patients in whom there was a clinical suspicion of ectopic pregnancy, 96 (24%) were found to have the condition. Of the 96, 70 underwent duplex Doppler imaging. A viable ectopic fetus was seen in 10 of 70 (14%), and an extrauterine sac without an identifiable fetus was seen in an additional 27, giving a sensitivity for imaging alone of 53%. Fetal heart activity was detected with Doppler in 13 (19%). High-velocity flow, which suggested the presence of an ectopic pregnancy, was detected in 38 of 70 (54%) patients (total preoperative sensitivity, 73%). In the 91 patients who did not have an ectopic pregnancy, duplex Doppler imaging of the intrauterine contents alone allowed an ectopic pregnancy to be excluded in 29 (32%) on the first examination and in a further 21 on the second scan (specificity, 55%). Nine vascular adnexal masses were falsely considered to be ectopic pregnancies (specificity, 90%). The positive predictive values were 47% for imaging alone and 85% for Doppler. The negative predictive values were 60% for imaging alone and 81% for Doppler.

Adult↗

PubMed1988

Tumor vascular signals in renal masses: detection with Doppler US.

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.

Adolescent↗