Renin-angiotensin-aldosterone system in long-term renal transplant patients

Seventeen anephric patients who constituted the subjects of this study received renal allografts between the years 1969 to 1973. The renin-angiotensin-aldosterone mechanism was evaluated in relation to either a normotensive or hypertensive clinical state in these subjects. Group I (Controls) were normotensive and on a normal diet; Group II were normotensive, on sodium restriction for five days, followed by saline infusion on the seventh day; and Group III were hypertensive, on similar sodium restriction for five days, followed by saline infusion on the seventh day. Glomerular filtration rates and levels of plasma renin and aldosterone, and the secretion rate of the latter were obtained on appropriate days. These studies confirm that an intact renin-angiotensin-aldosterone relationship exists in human renal transplant patients. The presence of high aldosterone secretion rate without hypertension is a new but unexplained finding. The lack of correlation of high aldosterone secretion rates in our normotensive and hypertensive patients suggests that aldosterone does not play a detectable or significant role in the pathogenesis of chronic or sustained transplant hypertension.     

Multispectral analysis of magnetic resonance images

Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.     

Parasitic infections in organ transplantation

More than 340 parasitic species infect more than 3 billion people worldwide with varying morbidity and mortality. The Tropics constitute the main reservoir of infection with the highest clinical impact, owing to favorable ecological factors. Acquisition of infection, clinical severity, and outcome of a parasitic disease depend on innate and acquired host immunity as well as the parasite's own immune response against the host when infection is established. Organ transplant recipients may acquire significant parasitic disease in 3 ways: transmission with the graft, de novo infection, or activation of dormant infection as a consequence of immunosuppression. Malaria, Trypanosoma, Toxoplasma, and Leishmania are the principal parasites that may be transmitted with bone marrow, kidney, or liver homografts, and microsporidia with xenotransplants. De novo infection with malaria and kala-azar may occur in immunocompromised travelers visiting in endemic areas, while immunocompromised natives are subject to superinfection with different strains of endemic parasites, reinfection with schistosomiasis, or rarely, with primary infections such as acanthamoeba. The list of parasites that may be reactivated in the immunocompromised host includes giardiasis, balantidiasis, strongyloidiasis, capillariasis, malaria, Chagas' disease, and kalaazar. The broad clinical syndromes of parasitic infection in transplant recipients include prolonged pyrexia, lower gastrointestinal symptoms, bronchopneumonia, and meningoencephalitis. Specific syndromes include the hematologic manifestations of malaria, myocarditis in Chagas' disease, acute renal failure in malaria and leishmaniasis, and the typical skin lesions of Chagas' and cutaneous leishmaniasis. Many antiparasitic drugs have the potential for gastrointestinal, hepatic, renal, and hematologic toxicity, and may interact with the metabolism of immunosuppressive agents. It is recommended that transplant clinicians have a high index of suspicion of parasitic infections as an important transmission threat, as well as a potential cause of significant posttransplant morbidity.     

Cervical changes associated with progestagen-only contraceptives: a team approach

OBJECTIVES: To report clinical, cytologic and colposcopic findings among women using progestagen-only contraceptives for more than 3 years as compared to nonhormonal contraceptives; and to assess the role of nursing in increasing the women's knowledge about Pap test and risk factors for cervical cancer in a developing country set-up. DESIGN: A prospective cross-sectional comparative study. SETTING: Family-planning clinic of a tertiary care university hospital. SUBJECTS: A total of 325 current users of contraceptive methods for more than 3 years. INTERVENTIONS: Patients were divided into two groups. Group A included 200 patients using progestagen-only contraceptives. While group B comprised 125 patients wearing intrauterine devices. In both groups, the patient was asked about the risk factors and her knowledge about cancer cervix. Clinical and cytologic evaluations of the cervix were done. For each patient, two cervical smears were taken using Ayre's spatula and the endocervical brush. MAIN OUTCOME MEASURES: Clinical, cytologic and histopathologic cervical abnormalities after prolonged use, and the effect of health education or counseling on the patient's knowledge about preinvasive or invasive cervical cancer. RESULTS: Initial naked eye assessment of the cervix revealed statistically significant difference between both groups (p < 0.000). However, cytologic examinations revealed positive cases of low- and high-grade squamous intraepithelial lesions (SIL) in 38 (19%) and 22 (17.6%) in the study and control groups, respectively, without any statistically significant difference. There were no statistically significant differences in both groups regarding the frequency of positive cases whether using Ayre's spatula or the endocervical brush. Women's knowledge was compared in the first and last interviews by the nursing staff involved in health education or counseling. It increased in the counseling group; however, the difference was statistically insignificant. CONCLUSIONS: Prolonged use of progestagen-only contraceptives is not associated with increased risk of abnormal cytologic findings. There was a marked lack of women's knowledge as regards Pap test and cervical cancer with some statistically insignificant improvement after interview and counseling. Extended training of the nursing staff on the procedure of Pap smear would help establish screening programs in the developing countries.     

Changes in intraocular pressure after laser in situ keratomileusis

PURPOSE: To evaluate changes in intraocular pressure (IOP) measurements by Goldmann applanation tonometry after laser in situ keratomileusis (LASIK) for myopia and myopic astigmatism, and to assess the accuracy of Goldmann applanation tonometry measurements after LASIK in these eyes. METHODS: LASIK was performed on 166 eyes of 93 patients for correction of myopia and myopic astigmatism. Intraocular pressure was measured by Goldmann applanation tonometry at the central and temporal parts of the cornea before and at 1, 3, 6, and 12 months after LASIK. The amount of change in IOP was computed and its relation to different variables was evaluated by regression analysis. RESULTS: Intraocular pressure measured at the center of the cornea was reduced by a mean of 3.69 +/- 1.63 mmHg after LASIK. Multiple regression analysis showed that the decrease in IOP was related to the preoperative IOP and the change in central corneal thickness after LASIK. Measurements of IOP at the temporal part of the cornea were also reduced by a mean of 2.39 +/- 1.71 mmHg. There was wide variability in the amount of difference between the temporal and central measurements after LASIK (temporal measurements were higher than central by 0 to +4 mmHg). CONCLUSION: LASIK for myopia produced underestimation of IOP measured by Goldmann applanation tonometry at the central part of the cornea by a mean of 3.69 +/- 1.63 mmHg. The decrease of IOP was related to preoperative IOP and the change in central corneal thickness after LASIK. Temporal Goldmann applanation tonometry measurements, although decreased after LASIK, were less reliable.     

Cardiac biopsy in childhood

Endomyocardial biopsy was attempted in 18 children aged 5 months to 15 years with 82% success. Biopsies obtained from 15 children were examined by light and electron microscope making positive morphological diagnoses in 3 cases. The biopsy findings were actively helpful in 7 other cases, which contrasts with experience in adult biopsy series. This is a low risk procedure which does not add to the hazards of cardiac catheterization in children.     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.