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D K Packham

Publications and source records attributed to D K Packham.

18 recordsLinked to original sources
PubMed1999

Response to parathyroidectomy at the axial and appendicular skeleton in renal patients.

AIM AND METHODS: We report increases in axial and appendicular bone density after parathyroidectomy in renal patients. Bone density was recorded pre-operatively and at 6 weeks, 6 months and 1 year post-operatively. We have previously reported that axial bone density increased dramatically at 6 weeks but that there were no early cohort increases at the appendicular skeleton [Stein et al. 1997]. RESULTS: We now report that at six months, bone density had continued to increase at the lumbar spine and femoral neck, with median respective 6 months increases over baseline of 1.3 (p < 0.01) and 0.7 (p < 0.01 ) Z-scores. Bone density then appeared to stabilize at the axial skeleton. At the appendicular skeleton increases were significant at the one year time point with median respective increases at the ultradistal radius and one third radius of 0.46 (p < 0.05) and 0.49 (p < 0.05) Z-scores. The different pattern of responses to parathyroidectomy between the axial and appendicular sites supports the concept that appendicular bone turnover is slower than axial bone turnover. Furthermore, at the appendicular skeleton, bone turnover appears similar between cortical and trabecular bone. CONCLUSION: In renal patients, bone density increases after parathyroidectomy at both the axial and appendicular skeleton. Axial increases are large and occur early. Appendicular increases occur at both cortical and trabecular sites but are slower than the axial changes.

Absorptiometry, Photon↗
PubMed1997

Large, rapid skeletal changes after parathyroidectomy.

We report dramatic increases in spine and hip bone mineral density six weeks following parathyroidectomy in renal patients. We have previously reported a cross-sectional association between parathyroidectomy and higher axial bone mineral density in dialysis patients. Large axial increases in bone mineral density after surgery for primary hyperparathyroidism have been recorded by others at one year postoperatively. Bone mineral density was recorded before and six weeks after parathyroidectomy. Scans were performed at the lumbar spine, hip and non-dominant radius. Values were expressed as Z-scores (standard deviations from the mean of an age- and gender-matched reference population). Large increases in lumbar were spine and femoral neck bone mineral density seen at six weeks post parathyroidectomy. Median increases were 0.57 (p = 0.006) and 0.26 (p = 0.039) Z-score units for these sites, respectively. Individual six-week increases were as large as 1.3 Z-score units at the spine and 1.0 Z-score units at the femoral neck. No significant cohort change was detected at the forearm but individual forearm changes were highly variable. Several mechanisms to explain these large rapid increases can be postulated. These include: mineralization of osteoid and/or contraction of the remodeling space. The changes illustrate the extent to which the skeleton is capable of rapid and profound change in mineral content. Our findings emphasize that the skeleton is a heterogeneous organ and that bone density should be measured at multiple skeletal sites.

Absorptiometry, Photon↗
PubMed1996

Prevalence and risk factors for osteopenia in dialysis patients.

Dialysis patients are at risk for low bone mineral density (BMD) consequent of hyperparathyroidism, 1,25-dihydroxyvitamin D deficiency, previous immunosuppression, chronic acidosis, secondary amenorrhea, and chronic heparin and aluminum exposure. We wanted to determine the prevalence and distribution of osteopenia and the influence of risk factors for osteopenia in dialysis patients. Dual energy x-ray absorptiometry was used to record BMD at the lumbar spine (LS), hip, and nondominant forearm. Results were expressed as Z-scores (standard deviations from the mean of a healthy age- and gender-matched reference population). Osteopenia was defined as a Z-score worse than -2. In the 250 dialysis patients studied, the prevalence of osteopenia at the LS, femoral neck (FN) and ultradistal radius (UD) was 8%, 13% and 20%, respectively. The median Z-scores at these sites were all significantly different from the healthy reference population median of 0 and were 0.29 (P = 0.008), -0.67 (P < 0.001), and -1.01 (P < 0.001), respectively. Previous transplantation was associated with as much as a one Z-score lower BMD at the FN (P = 0.0069) and UD (P = 0.0011) and a marginally significant reduction at the LS (P = 0.0777). Previous parathyroidectomy was associated with a markedly higher LS BMD (P = 0.0001) and a higher BMD at the FN (P = 0.0017) but not the UD (P = 0.3691). A history of secondary amenorrhea was associated with a lower FN BMD (P = 0.0047) but not a significantly lower BMD at the LS (P = 0.0978) or UD (P = 0.2327). In hemodialysis patients without a history of transplantation, parathyroidectomy, or secondary amenorrhea, there was no correlation between Z-score at any site and duration of dialysis. Thus, osteopenia in dialysis patients occurs in both axial and appendicular sites and sites of compact and cancellous bone. It is more common with previous transplantation and secondary amenorrhea, whereas a history of parathyroidectomy is associated with increased BMD. No relationship was found between BMD and duration of hemodialysis, which suggests that important changes in BMD occur during the predialysis stage of chronic renal failure.

Absorptiometry, Photon↗
PubMed1996

The significance of focal and segmental hyalinosis and sclerosis (FSHS) and nephrotic range proteinuria in IgA nephropathy.

Between 1971 and 1991, 845 patients were diagnosed as having IgA glomerulonephritis on renal biopsy performed. These patients were followed for a mean period of 53 months post biopsy (range 0-336 months). By the end of follow up 147 (17%) of patients have developed chronic renal failure (Cr > 0.2 mmol/l) or end-stage renal failure. Presenting creatinine > 0.12 mmol/l, hypertension, nephrotic range, age > 40 years and male gender, all correlated strongly on univariate analysis with the development of chronic renal failure or kidney disease (all p < 0.0001). However, a number of patients developing chronic renal failure or end-stage renal failure already had renal impairment (creatinine > 0.12 mmol/l at presentation). A separate comparison was performed of patients presenting with creatinine < 0.12 mmol/l and either developing chronic failure or end-stage renal failure within 5 years of biopsy (n = 18) and those with creatinine still < 0.12 mmol/l after 5 years follow up (n = 186). Of the 18 patients who deteriorated 6 (35%) were nephrotic at presentation and 9 (56%) had focal hyalinosis and sclerosis on renal biopsy. This compared with 5 (3%) patients with nephrotic range proteinuria and 16 (10%) patients with focal hyalinosis and sclerosis among the 186 patients who did not deteriorate (p < 0.0001). The sensitivity and specificity of the presence of either or both factors in predicting deterioration was calculated at 65% and 87% respectively. Thus in patients with normal renal function at presentation the presence of nephrotic range or focal hyalinosis and sclerosis are strong predictors of adverse clinical outcome.

Adult↗
PubMed1994

Acute renal failure in IgA nephropathy.

Twenty-five (3%) of 865 patients with IgA nephropathy presented with acute renal failure (ARF). These patients were matched with 25 patients in the same series who presented with irreversible renal impairment. Patients with acute renal failure had a significantly higher incidence of macroscopic hematuria and red blood cells in tubules. Conversely, a greater percentage of patients with irreversible renal failure had > or = 40% sclerosed glomeruli. The long-term prognosis for patients presenting with ARF appears excellent with only 1 (4%) patient developing chronic renal failure after a mean follow-up of 65 months. Mechanisms of acute renal failure in IgA nephropathy are discussed.

Acute Kidney Injury↗
PubMed1994

Pregnancy-related complications in women with reflux nephropathy.

Three hundred and forty-five pregnancies in 137 women with reflux nephropathy have been studied. All pregnancies took place after 1971. Overall foetal loss was 48 (14%) of which only 6 (2%) were therapeutic abortions. Maternal complications (urine infection, hypertension, proteinuria, oedema, deterioration in renal function, hematuria or renal stones) occurred alone or in combination in 39% of pregnancies. Fifty-two pregnancies took place in women with plasma creatinine (P.Cr > 0.11 mmol/l) prior to conception. Foetal loss after 12 weeks gestation (excluding therapeutic abortions) was 18% compared with 8% in the 104 pregnancies where maternal P.Cr was known to be < or = o.11 per/l at conception (p < 0.05). Maternal complications were also more common in the impaired renal function group (p < 0.001). Comparison of pregnancies in women with unilateral versus bilateral renal scarring revealed no significant difference in foetal loss but an increased incidence of over 50% maternal complications in the bilateral renal scar group (p < 0.01). The incidence of pre-eclampsia was higher in women with bilateral renal scars, 50 (24%) than in women with unilateral scars 8 (7%) (p < 0.001). Persistent vesicoureteric reflux was not associated with increased foetal loss or maternal risk. Impaired renal function prior to conception is associated with increased foetal and maternal complications in pregnancy. Bilateral renal scarring is associated with increased maternal complications during pregnancy.

Abortion, Spontaneous↗
PubMed1992

Glomerulosclerosis and hyalinosis in rabbits.

Histological appearances of remnant kidney in female New Zealand white rabbits undergoing left nephrectomy at 6 mths were studied. All 20 rabbits had evidence of previous Encephalitozoon cuniculi (E. cuniculi) infection. Half of the 10 uninephrectomized and 10 control animals completed 3 pregnancies before sacrifice (15 mths). Twelve of 30 kidneys at sacrifice showed focal and segmental hyalinosis and sclerosis (FSHS), a lesion not previously reported in rabbits. Four of 5 kidneys in both uninephrectomized pregnant and uninephrectomized virgin animals showed FSHS compared with 2 of 10 in both control pregnant and non-pregnant rabbits (p = 0.0026). More glomeruli were sclerosed in control pregnant (median 3.5%) than non pregnant animals (median 0.4%) (p < 0.005). Median right kidney weights per kilogram body weight were greater in previously nephrectomized animals (3.9 gm/kg) than controls (2.6 gm/kg), (p < 0.001). Absolute glomerular area was increased in hypertrophied kidneys, however, after correction for kidney weight, glomerular area was smaller in previously uninephrectomized animals than controls (p < 0.0001).

Animals↗
PubMed1992

Lupus nephritis and pregnancy.

Sixty-four pregnancies in 41 women with biopsy proven lupus nephritis between 1965 and 1991 were analysed to record fetal and maternal outcome and identify risk factors for poor outcome. Of 65 fetuses, 22 (34 per cent) were lost (including therapeutic abortions), 19 (30 per cent) were live born but premature (less than or equal to 36 weeks gestation) and 24 (37 per cent) were term. Fetal loss after 20 weeks gestation was 19 per cent. Twelve per cent of 25 fetuses whose birthweight was recorded were small for gestational age. Maternal renal function deteriorated in 19 per cent of pregnancies but was irreversible post-partum in only one woman (2 per cent). Hypertension was recorded in 44 per cent of pregnancies, developed early (less than or equal to 32 weeks gestation) in 28 per cent and was severe in 13 per cent. Treated hypertension predated 17 per cent of pregnancies and in 6 per cent (included in the overall incidence of hypertension) exacerbation occurred during pregnancy despite continued anti-hypertensive medication. Nine women (22 per cent) who developed de novo hypertension in pregnancy had permanent hypertension post-partum. Increased proteinuria was recorded in 48 per cent of pregnancies and was irreversible post partum in 5 per cent. Comparison of pregnancies occurring before or after diagnosis was made by renal biopsy failed to show any significant difference in fetal outcome. Pregnancies occurring after the diagnosis of glomerulonephritis were associated with a significantly lower incidence of maternal hypertension, early hypertension, severe hypertension and increased proteinuria. The presence of the circulating lupus anticoagulant was clearly associated with a significantly high fetal loss rate although the incidence of maternal complications did not differ significantly between mothers positive or negative for lupus anticoagulant.

Abortion, Spontaneous↗
PubMed1989

Primary glomerulonephritis and pregnancy.

Three hundred and ninety-five pregnancies undertaken by 238 women with primary glomerulonephritis between 1962 and 1987 were analysed to record fetal and maternal outcome and identify risk factors for a poor outcome. Of 398 fetuses, 26 per cent were lost (including therapeutic abortions), 24 per cent surviving infants were premature (less than or equal to 36 weeks gestation) and 51 per cent were term. Excluding therapeutic abortions, 20 per cent of fetuses were lost, 15 per cent after 20 weeks gestation. Fifteen per cent of 237 fetuses whose birth weight was recorded were small for gestational age: Deterioration in maternal renal function was seen in 15 per cent of pregnancies and in 5 per cent of women failed to resolve post partum. Only four women had impaired renal function recorded in the first-trimester and two of these were known to have renal impairment before pregnancy. Hypertension was recorded in 52 per cent of pregnancies, developed early (less than or equal to 32 weeks gestation) in 26 per cent and was severe in 18 per cent. Treated hypertension pre-dated 12 per cent of pregnancies and in 7 per cent (included in the overall incidence of hypertension) exacerbation occurred during pregnancy despite continued antihypertensive medication. Forty-four women (18 per cent) who developed de novo hypertension in pregnancy had permanent hypertension postpartum. Increased proteinuria was recorded in 59 per cent of pregnancies and was irreversible in 15 per cent of women. Comparison of pregnancies which occurred before or after renal biopsy revealed a significantly higher fetal loss rate after 20 weeks gestation in those pregnancies undertaken before the diagnosis of renal disease, and a significantly higher incidence of hypertension and increased proteinuria. Impaired renal function, early or severe hypertension or nephrotic range proteinuria was significantly associated with increased fetal loss, prematurity and fewer full-term infants. There was no significant difference in fetal outcome or maternal complications in pregnancy in patients with treated hypertension before pregnancy and those who were normotensive in the first-trimester. The highest incidence of fetal and maternal complications occurred in patients with primary focal and segmental hyalinosis and sclerosis and the lowest in non-IgA diffuse mesangial proliferative glomerulonephritis. The presence of severe vessel lesions on renal biopsy was associated with a significantly higher total fetal loss and fetal loss after 20 weeks gestation.

Female↗
PubMed1988

Morphometric analysis of pre-eclampsia in women biopsied in pregnancy and post-partum.

The importance of endothelial cell swelling and subepithelial deposits in producing capillary wall thickening in women with pre-eclampsia is controversial. In this study renal biopsy tissue from 16 women with a diagnosis of pre-eclampsia was analyzed morphometrically. Women biopsied during pregnancy (N = 6) showed substantial, electron-dense subendothelial deposits in capillary loops, but these were rare or absent in women (N = 10) biopsied post-partum (P less than 0.01). Endothelial cell swelling was present in both groups of patients to an equal degree. Mesangial cell interposition occurred but was not the dominant feature, and was similar in both pregnancy and post-partum biopsies. The median percentage per patient occupied by basement membrane was similar for both groups. Subendothelial deposits appear to resolve early in the post-partum period.

Adult↗
PubMed1988

Pregnancy in women with primary focal and segmental hyalinosis and sclerosis.

Thirty-one pregnancies and post partum clinical course of 21 women with a diagnosis of primary focal and segmental hyalinosis and sclerosis have been analyzed. Forty-five percent (14) of pregnancies resulted in fetal loss, 39% (12) in premature delivery and 16% (5) in a term infant. Of 17 fetuses for whom birthweight was recorded, 29% (5) were small for gestational age. Maternal renal function deteriorated in 49% (15) of pregnancies, in 13% (4) irreversibly. Three of these patients (15%) subsequently progressed to end-stage renal failure, and one to progressive chronic renal impairment, by the end of follow-up (median 4 years, range 1-25 years). In 74% (23) of pregnancies hypertension was recorded and this frequently developed early (61%) and was severe (45%). Nephrotic range proteinuria developed in 42% (13) of pregnancies. Increased proteinuria was recorded in 22 (17%) pregnancies. It is concluded that pregnancy in women with primary focal and segmental hyalinosis and sclerosis is associated with increased fetal loss and maternal complications.

Adult↗
PubMed1988

IgA glomerulonephritis and pregnancy.

One hundred and sixteen pregnancies in 70 women with a biopsy-proven diagnosis of IgA glomerulonephritis have been analysed. Thirty percent (35) of the fetuses died, 22% (26) were premature and 44% (52) were full term. Maternal renal function declined during pregnancy in 26% (30) and in 2% (2) this was irreversible post-partum. Hypertension developed in 52% (61) of the pregnancies and in 13% (15) this was irreversible. Increased proteinuria was recorded in 62% (74) of the pregnancies. Fetal loss in pregnancies taking place after biopsy diagnosis was lower (16%) than those in which biopsy was performed either during or following the pregnancy (36%).

Abortion, Habitual↗
PubMed1988

Pregnancy in women with diffuse mesangial proliferative glomerulonephritis.

The clinical course of 168 pregnancies in 91 women with non-IgA diffuse mesangial proliferative glomerulonephritis has been analyzed. Twenty percent (33) of pregnancies resulted in fetal loss, 18% (31) in premature delivery and 62% (105) in a term infant. Maternal renal function declined, reversibly, in 3% (5) of pregnancies and in 48% (80) hypertension developed. In 53% (89) a significant increase in proteinuria occurred in pregnancy. Fetal and maternal complications of pregnancy occurred more frequently in patients with pre-existing hypertension although differences failed to reach statistical significance (p greater than 0.01). The presence of severe vessel lesions on the diagnostic renal biopsy was associated with a significantly higher fetal loss and prematurity rate (p less than 0.0005 and p less than 0.005, respectively).

Female↗
PubMed1987

Membranous glomerulonephritis and pregnancy.

The clinical courses of 33 pregnancies in 24 patients with biopsy proven membranous glomerulonephritis have been analyzed. Twenty-four percent (8) of pregnancies resulted in fetal loss, 43% (14) in premature delivery and 33% (11) in a live birth after 36 weeks gestation. Maternal renal function declined during pregnancy in 9% (3) of the pregnancies and in 46% (15) hypertension developed. In 55% (18) proteinuria increased significantly during pregnancy. In 30% (10) nephrotic range proteinuria was recorded in the first trimester. Presence of nephrotic range proteinuria during the first trimester correlated with both poor fetal and poor maternal outcome (p less than 0.0004 and p less than 0.0002, respectively). It is concluded that pregnancy in patients with membranous glomerulonephritis is associated with increased fetal loss and, in some instances, a worsening in maternal renal function. The literature on this topic is reviewed in relation to these findings.

Female↗