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J M Davison

Publications and source records attributed to J M Davison.

At least 91 records · Page 5Linked to original sources
PubMed1987

Pregnancy in renal allograft recipients: prognosis and management.

Renal transplantation is invariably accompanied by improvements in reproductive function. The possibility of conception in women of childbearing age emphasizes the need for compassionate and comprehensive counselling. Couples who want a child should be encouraged to discuss all the implications. Therapeutic abortion is undertaken in 22% of conceptions and the spontaneous abortion rate is about 16%, the same as for the normal population. Of the conceptions that continue beyond the first trimester, over 90% end successfully. In most women, renal function is augmented during pregnancy, but permanent impairment occurs in 15% of pregnancies. In others there may be transient deterioration in late pregnancy (with or without proteinuria). There is a 30% chance of developing hypertension, pre-eclampsia or both. Preterm delivery occurs in 45-60%, and intrauterine growth retardation in at least 20% of pregnancies. Despite its pelvic location, the transplanted kidney rarely produces dystocia and is not injured during vaginal delivery. Caesarean section should be reserved for obstetric reasons only. Neonatal complications include respiratory distress syndrome, leucopaenia, thrombocytopaenia, adrenocortical insufficiency and infection. No predominant or frequent developmental abnormalities have been described and data on infancy and childhood are encouraging. For the future, clinical and laboratory research are essential in order to improve prepregnancy assessment criteria, to understand the mechanisms of gestational renal dysfunction and proteinuria, to assess the side-effects and implications of immunosuppression in pregnancy and to learn more about the remote effects of pregnancy on both renal prognosis and the offspring.

Female↗
PubMed1987

Human parvovirus B19 infection during pregnancy.

Human parvovirus B19 (B19) has been implicated as the cause of fifth disease and has been associated with fetal death. We identified pregnant women who were at risk of contracting B19 infection during an outbreak of fifth disease. The sera of 12 women classified at high risk of exposure and 19 classified at low risk were tested during prenatal care, at delivery, or at both times for IgG and IgM antibodies to B19. Four women at high risk but none at low risk were considered infected because they were IgM positive. One IgM-positive woman gave birth to a stillborn hydropic fetus whose tissues were positive for B19 DNA by a nucleic acid hybridization assay. The other three IgM-positive women gave birth to normal offspring, of whom one had IgM-positive cord serum. We conclude that B19 infection during pregnancy can lead to fetal infection with at least two associated outcomes--no adverse effect on the fetus or fetal death.

Adolescent↗
PubMed1985

The effect of pregnancy on kidney function in renal allograft recipients.

In women with renal transplants glomerular filtration rate (GFR) increases during pregnancy but how soon the increment occurs, its relation to pre-pregnancy GFR, and the overall pattern of change are unknown. Twenty-four hour creatinine clearance (24-hr CCr) were measured prospectively in ten pregnancies in eight allograft recipients before conception, throughout pregnancy, 8 to 12 weeks postpartum, and 4 to 6 monthly thereafter. Inulin (CIn) in creatinine (CCr) clearances during infusion were also determined and protein excretion was evaluated. The results were compared to those in similar studies in ten healthy women. By the tenth gestational week 24-hr CCr was 124 +/- (SD) 15.9 ml/min in healthy women (an increase of 38%; range, 18 to 69%) and in transplant patients was 105 +/- 28.1 ml/min (an increase of 34%: range, 10 to 60%), with the greatest increments in those whose allografts functioned best before conception, regardless of donor source and sex or the transplant-pregnancy interval. In late pregnancy mean 24-hr CCr decreased by 19% (range, 6 to 28%) in healthy women and by 34% (range, 12 to 57%) in the transplant patients, but in most this did not represent graft deterioration nor lead to permanent impairment. At all time points CIn values were 5 to 10% greater than those for 24-hr CCr but slightly less than infusion CCr values. Protein excretion increased throughout pregnancy and by the third trimester in healthy women averaged 200 mg in 24 hr and regularly exceeded 500 mg in 24 hr in transplant patients, which was three times non-pregnant levels and probably not clinically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

Maternal azathioprine therapy and depressed haemopoiesis in the babies of renal allograft patients.

Maternal immunosuppression with azathioprine during pregnancy can depress fetal haemopoiesis resulting in neonatal thrombocytopenia and leucopenia with the potential for serious sequelae. The effect on the infant of adjusting azathioprine dosage on the basis of maternal total leucocyte count has been studied in 10 pregnancies in eight renal allograft recipients. Throughout the first six pregnancies azathioprine dosage was unchanged and although the characteristic pregnancy leucocytosis was evident it was not maintained in four patients whose leucocyte counts by 32 weeks gestation were significantly less than our norm [10.3 (SD 1.7) X 10(9)/1] and who subsequently had babies with cord leucocyte counts less than or equal to 8.0 X 10(9)/l, again significantly less than our norm [13.7 (SD 3.9) X 10(9)/l]. A significant correlation existed between maternal leucocyte counts at 32 weeks gestation and at delivery and cord leucocyte count (r = 0.847; P less than 0.01 and r = 0.915; P less than 0.01 respectively). Three of these infants had platelet counts less than or equal to 100 X 10(9)/l but there was no correlation between maternal platelet counts at 32 weeks gestation or at delivery and cord platelet count. For the next four pregnancies policy changed: at 32 weeks gestation azathioprine dosage was halved if maternal leucocyte count was at or below the 1SD band (8.6 X 10(9)/l) for normal pregnancy. All of the infants were haemotologically normal and two patients whose first babies had leucopenia and thrombocytopenia had second babies without problems. Analysis of data from all 10 pregnancies still demonstrated a significant correlation between cord leucocyte count and maternal leucocyte count at delivery but no longer at 32 weeks gestation.(ABSTRACT TRUNCATED AT 250 WORDS)

Azathioprine↗
PubMed1985

Kidney disease and pregnancy: obstetric outcome and long-term renal prognosis.

In patients with chronic renal disease, all advice and decisions must take into account the balance between pregnancy outcome and the long-term impact that pregnancy might have on the disease. To help the clinician address these concerns, the authors focus on the renal changes in normal pregnancy, the problems of chronic renal disease in pregnancy, and the effect pregnancy has on long-term renal prognosis.

Female↗
PubMed1984

The effect of covert bacteriuria in schoolgirls on renal function at 18 years and during pregnancy.

Schoolgirls shown to have covert bacteriuria (CB) by a screening programme and followed up for 5 years to assess whether chemotherapy had any beneficial effect, underwent a further assessment of renal function at the age of 18 years and during subsequent pregnancies. At age 18, glomerular filtration rate (GFR) and urine concentrating ability were the same as in controls, but fractional reabsorption of glucose was significantly reduced in those who had previously been prescribed chemotherapy because of renal scarring or who had been randomly allocated not to receive prophylactic chemotherapy. Those who had had CB as schoolgirls had a higher frequency of CB in pregnancy than did controls, whether or not prophylactic chemotherapy had been given to the subjects when they were schoolgirls. Furthermore, compared with girls who had had such treatment, untreated patients had smaller increments in GFR, reduced fractional reabsorption of glucose, and more than usual degree of glycosuria during pregnancy. This suggests that subclinical renal damage may be prevented by prophylactic chemotherapy but this advantage is unmasked only by the physiological demands of pregnancy.

Adolescent↗
PubMed1984

Altered osmotic thresholds for vasopressin secretion and thirst in human pregnancy.

Osmoregulation was studied in eight women during late pregnancy and again 8-10 wk postpartum. Base-line plasma osmolality (Posmol) was significantly lower during (280.9 +/- 2.1 mosmol/kg, SD) than after (289.4 +/- 2.1 mosmol/kg) pregnancy yet 24-h urinary volume and plasma arginine vasopressin (PAVP) measured in vasopressinase-inactivated blood was similar in both groups (pregnancy, 1.39 +/- 0.56 pg/ml; postpartum, 1.25 +/- 0.62 pg/ml). After 12 h of dehydration PAVP rose similarly and significantly both during (2.25 +/- 0.81 pg/ml) and after (2.89 +/- 1.19 pg/ml) gestation, and Uosmol was similar on both occasions (pregnancy, 779 +/- 121 mosmol/kg; postpartum, 784 +/- 102 mosmol/kg). When Posmol was increased by the slow infusion of 5% saline PAVP increased as soon as body tonicity did both during and after pregnancy. PAVP correlated significantly with Posmol in each subject (range of r, 0.75-0.99) and the mean regression lines [pregnancy, PAVP = 0.32 (Posmol; -279), r = 0.79; postpartum, PAVP = 0.38 (Posmol, -285), r = 0.86] demonstrated that the apparent osmotic threshold for AVP secretion was 6 mosmol/kg lower during than after gestation. Similarly the Posmol at which the subject experienced a conscious desire to drink was lower in pregnant (287 +/- 1.6 mosmol/kg) compared with postpartum subjects (298 +/- 2.0 mosmol/kg; P less than 0.001). These data demonstrate decreased osmotic thresholds for AVP release and thirst during human pregnancy and explain why gravidas can maintain their new lower Posmol within narrow limits.

Adult↗