Long-term continuous ambulatory peritoneal dialysis in diabetics.

Of 147 diabetic patients with end-stage renal disease who were treated in our CAPD program between 1978 and 1991, 6 men and 1 woman (5 had type II and 2 type I diabetes) with a mean age of 54 (range 21-70) years have been on CAPD for more than five years (mean: 76 mos, range: 65-109 mos) and on peritoneal dialysis (IPD+CAPD) for an average of 85 (range: 67-118) mos. They had a variety of comorbid conditions at the start of CAPD: Retinopathy (5/7), blindness (3/7), hypertension (5/7), peripheral neuropathy (7/7), peripheral vascular disease (3/7), congestive heart failure (3/7), myocardial infarction (1/7), ischemic heart disease (2/7). Two were smokers and five over the age of 65. Peritonitis rate was 1 episode/11.4 pt mos, exit-site infection 1/76.4 pt mos and average hospitalization rate 32.8 days/patient/year. Hypertension was well-controlled with discontinuation of all medications; after initiation of CAPD two of them remained without medications throughout the study but in the rest, medications had to be restarted. As assessed by HbA1c, blood glucose control improved with IP administration of insulin. Residual renal function progressively decreased. None of them developed severe hyperparathyroidism. Peripheral neuropathy remained stable in four and deteriorated in two. Total protein, albumin, cholesterol and triglycerides decreased during the last two years indicating a degree of malnutrition. Our experience with these seven patients suggests that diabetic patients, even the aged and those with many comorbid conditions and complications, can survive for long periods on CAPD.

Advantages of peripheral radiogrametry over dual-photon absorptiometry of the spine in the assessment of prevalence of osteoporotic vertebral fractures in women.

Since osteoporosis develops in most postmenopausal women and is probably the most important single factor in the pathogenesis of osteoporotic fractures of the spine, hip, and wrist (and at other sites), methods suitable for mass screening should be developed. In this study of 97 women aged 24-79, measurements of the lumbar spine mineral content by dual-photon absorptiometry (DPA) were compared with the summed combined cortical thickness measurements from radiographs of the radius and metacarpal II (MR). There was good correlation between the two methods (r = 0.90). The correlation of age with MR was higher than with DPA. The correlation of years postmenopause was significant with MR but not with DPA. Taking the -2 SD level of the premenopausal means to be previously established vertebral fracture thresholds, 24% of the DPA measurements, but no MR measurements in patients with vertebral compressions, were above the fracture threshold. Since MR measurement requires taking only two small plain radiographs using ordinary x-ray equipment, it is concluded that this less expensive method is better suited to screening for osteoporotic vertebral fracture risk in postmenopausal women than DPA.

Radiologic study of endosteal, intracortical, and periosteal surfaces of hand bones in metabolic bone diseases.

In metabolic bone diseases, subtle abnormalities occur on the three surfaces of bone, the recognition of which is important for diagnosis, as well as in follow-up studies, to recognize progression or regression. These resorptive and formative changes are best studied in fine-detail hand radiographs under 6 to 8 times magnification by a relatively simple radiologic method (microradioscopy). The periosteal resorption of hyperparathyroidism is thus recognized earlier than by regular radiography, and intracortical resorption, not detectable by the naked eye, can be visualized. The latter is also seen frequently in nutritional osteomalcia, renal osteodystrophy, and thyrotoxicosis, and sometimes in acromegaly. Endosteal resorption in developing involutional osteoporosis can also be recognized more efficiently by microradioscopy than by ordinary radiographs without magnification. Fine-detail hand radiographs may thus be used as an inexpensive preliminary measurement for diagnosis of osteoporosis.

Improved vertebral fracture threshold in postmenopausal osteoporosis by radiogrametric measurements: its usefulness in selection for preventive therapy.

Measurements of the combined cortical thickness at the midshafts of the second metacarpal and the proximal radius, as well as their sums, were made from fine-grained radiographs in 107 normal premenopausal and 227 postmenopausal women and in 57 women with at least two spontaneous vertebral compressions. The -2 SD level of the premenopausal women was found to be an excellent vertebral fracture threshold for the radius measuring site and for the sums of metacarpal and radial measurements. Only 2 of 57 (4%) and 3 of 57 (5%), respectively, of values in the vertebral compression group fell at or above this level. At -3 SD a "secondary fracture threshold" was found for the sums in that only 7 of 57 (12%) of values in women with vertebral compressions were above this limit, but -3 SD was less satisfactory for the radius. We conclude that this method discriminates as well between nonfracture and fracture cases as other radiologic methods for measurement of bone mass or density. Because it is less costly it seems better suited for mass screening in selecting postmenopausal women for preventive therapy than the less widely available high-technology methods.

Oxalate bone disease--an emerging form of renal osteodystrophy.

Rosette-like arrays of highly birefringent calcium oxalate crystals are commonly seen in the marrow space of bone biopsy specimens taken from patients with primary hyperoxaluria, particularly if complicated by renal failure. Similar deposits have been described in chronic hemodialysis patients with secondary forms of oxalosis. Large multinucleated histiocytes may be seen surrounding these crystal deposits. Many of these cells are histologically indistinguishable from osteoclasts. We present a patient in whom this histiocytic reaction appeared to be of sufficient magnitude to stimulate bone resorption and to cause severe osteodystrophy. This observation, and those of other investigators reviewed in the discussion, suggest that oxalate deposition within bone may contribute to the pathogenesis of uremic osteodystrophy in chronic renal failure patients with primary or secondary types of oxalosis.

Serum magnesium level and arterial calcification in end-stage renal disease.

In this paper we examine the relationship of serum levels of Ca, P, Ca X P, P/Mg, Ca X P/Mg, alkaline phosphatase, and iPTH to the development or regression of peripheral arterial calcifications (AC) in 44 patients with end-stage renal disease being treated by continuous ambulatory peritoneal dialysis (CAPD). The average follow-up time of this longitudinal study was 27 months (range 6-67 months). The patients were divided into two groups: Group A, those showing one or more increases of AC; and Group B, patients in whom AC either did not develop or decreased during the follow-up. There was no significant difference in serum Ca, P, Ca X P, alkaline phosphatase of iPTH between the two groups. However, serum Mg was significantly lower in Group A than in Group B (2.69 +/- 0.52 and 3.02 +/- 0.51 mg/dl, respectively, P less than 0.001), while the ratios P/Mg and Ca X P/Mg were significantly higher. Our observations suggest that in end-stage renal disease hypermagnesemia may retard the development of arterial calcifications.

Postmenopausal osteoporosis: simple screening method for diagnosis before structural failure.

Concurrent measurements of combined cortical thickness (CCT) at the midshaft of the second metacarpal and at the proximal juxtametaphyseal radial cortex were made in 234 healthy women aged 46-80 years (group 1) and in 52 women with symptomatic osteoporosis (at least two spontaneous vertebral compressions) (group 2). When -2 standard deviations (SDs) of the mean values in young healthy women (aged 21-45 years) were used as the lower limit of normal measurements, 47% of the subjects in group 1 showed abnormalities: in 25% both bones were abnormal, in 12% the radius alone was abnormal, and in 10% the second metacarpal alone was abnormal. Because 98% of the subjects in group 2 had abnormal CCT measurements, the -2-SD limit of the younger healthy subjects appears to constitute a satisfactory "fracture threshold." Although further research and correlation are required, these simple and inexpensive measurements may be appropriate for mass screening to separate those at greater risk for development of spontaneous vertebral compressions from those at lesser risk.

Longitudinal microradioscopic comparisons on endosteal and juxtaendosteal bone loss in premenopausal and postmenopausal women, and in those with end-stage renal disease.

Endosteal bone resorption is the principal mechanism of bone loss in involutional osteoporosis and in renal osteodystrophy. In the cortical bone it is often accompanied by juxtaendostal bone resorption. Using fine-detail radiographs and x6 magnified viewing, longitudinal radiographic observations and measurements were made on these two forms of bone resorption in the metacarpals II, III, and IV in three groups of women: (1) premenopausal, (2) postmenopausal, and (3) patients with end-stage renal disease. Bone loss was found to be negligible in the premenopausal women, but in postmenopausal and renal patients both endosteal and juxtaendosteal bone resorption were frequently demonstrable. It is suggested that when a base-line fine-detail hand radiograph is obtained at the time of the menopause, follow-up radiographs may permit detection of relatively early endosteal and juxtaendosteal bone loss by comparing the respective areas in metacarpals with those of the original radiograph. Since the methodology does not require expensive equipment, has a low intraobserver error and is simple to perform, it may deserve to be further evaluated in studies aimed at developing a simple and inexpensive approach as a screening method for early detection of postmenopausal osteoporosis.

Radiographically detectable intracortical porosity. The dimensions and frequencies of its components in hand bones of normal men and women.

Since the measurement of intracortical resorptive spaces by histologic methods is difficult and very few data are available in normal humans, we have measured their lengths and widths and calculated the intracortical porosity in metacarpals and phalanges of 79 normal women and 69 normal men, using fine-detail radiographs of the hands and a computerized semi-automatic image analysis system (Zeiss MOP-3), this being the first study of this kind. Several methodological problems were solved satisfactorily, and the results of this study could serve as a data bank for further investigations concerned with intracortical resorption. Significant differences were found between age and sex versus several intracortical resorptive parameters; also significant correlations were found with age in some cases. Normal intracortical porosity was found to be about three times greater in the proximal phalanges than in the metacarpals. It is concluded that this methodology could be used for further studies of intracortical resorption in osteoporosis and other metabolic bone diseases.

Morphology, progression, and regression of arterial and periarterial calcifications in patients with end-stage renal disease.

The appearance of arterial calcifications over time was studied radiographically in 143 patients with end-stage renal disease. Of these, 85 patients had only slight calcifications; 58 had the well-known, linear, pipe stem-like arterial calcifications. In 44 of the 58, small nodular calcifications were noted, often external to the linear calcifications. Nine patients had larger periarterial calcifications, which have not been previously described to our knowledge. Arterial calcifications progressed in 82 of 143 patients (57%) and regressed in 19 (13%). During progression, thickening of the linear calcifications was often observed, and in ten patients this caused definite luminal narrowing. From 1976 to 1984, five of 71 patients (7%) required amputations; all five had marked arterial calcifications. Better controlled clinical studies are indicated to detect factors that may prevent the progression and promote the regression of arterial calcifications.

Periosteal resorption and periosteal neostosis: comparison of normal subjects and renal failure patients on chronic ambulatory peritoneal dialysis using MOP-3 image analysis system and a grading method.

This is the first known attempt to quantitate periosteal resorption (PR) and perisoteal neostosis (PN) by a semi-automatic image analysis system (Zeiss MOP-3). The normal ranges and errors for PR were found to be similar to those of a previous study using a measuring magnifier. The findings in chronic renal failure patients showed that MOP-3 measurements were actually diagnostically slightly less sensitive than the results by a simple grading method. Comparison with plasma-immunoreactive parathyroid hormone (iPTH) concentrations showed that while the latter had a higher sensitivity for detection of hyperparathyroidism, the radiologic parameters nevertheless showed abnormal PR in 12% of the observations where iPTH was normal. Both PR and PN correlated significantly with iPTH (r = 0.55 and 0.30 respectively, P less than 0.01).

Quantitative radionuclide scanning in metabolic bone disease.

A simple method of quantifying skeletal uptake of 99Tcm-methylene diphosphonate, using a rectilinear scanner and a simultaneously image standard, is described. The pattern of quantified uptake in ten regions of the skeleton, the sacro-iliac joints and kidneys in 57 controls and 54 patients with various metabolic bone disease is presented. This method distinguishes patients with primary hyperparathyroidism and osteomalacia from controls with a sensitivity adequate for clinical purposes. In primary hyperparathyroidism the increased skull uptake of tracer correlated well with levels of serum alkaline phosphatase, plasma parathyroid hormone, urinary hydroxyproline excretion and the degree of intracortical resorption in the metacarpal bones. The skull uptake in oestoporosis was normal or moderately elevated and correlated well with bone mass density measurements of the radius. Patients with osteomalacia also showed the greatest increase in tracer uptake in the skull. Patients with thyrotoxicosis differed from most other patients by showing moderately increased uptake in shafts of long bones. We propose our method of quantitative bone uptake as a useful noninvasive test to detect metabolic bone disease and to monitor responses to therapy of bone disease.

The influence of age and sex on bone resorption of secondary hyperparathyroidism in renal osteodystrophy.

The severity and incidence of subperiosteal and intracortical bone resorption were evaluated from fine-detail hand radiographs at X 8 magnification in relation to age and sex in 239 chronically dialyzed adult renal failure patients. The severity of subperiosteal resorption decreased significantly with advancing age in both sexes and the incidence decreased somewhat more in males than in females; no such trends were apparent for intracortical resorption. Although the mean values for the grades of subperiosteal and intracortical resorption were significantly higher in females than in males, when the effect of age and duration of follow-up were taken into consideration, this sex difference remained significant only for intracortical resorption. It is concluded that when studying certain aspects of renal osteodystrophy, differences due to age, sex, and duration of follow-up should be considered in the final interpretation of data.

The mode of progression of subperiosteal resorption in the hyperparathyroidism of chronic renal failure.

Subperiosteal resorption in finger phalanges is usually thought to be the result of osteoclastic bone resorption on the periosteal surface of bone, progressive centripetally, with creation of the serrated appearances and "lace-like" patterns in periosteal cortical bone. Our longitudinal microradioscopic observations in patients with secondary hyperparathyroidism of chronic renal failure have revealed evidence of another pathogenetic mechanism: by the enlargement of intracortical juxtaperiosteal resorption spaces, the remaining thin layer of bone is broken down from inside the bone, i.e., a centrifugal rather than centripetal process.

Evaluation of cortical bone mass, thickness and density by z-scores in osteopenic conditions and in relation to menopause and estrogen treatment.

Z-scores express differences from normals in standard deviation units, and are particularly useful for comparison of changes where normal values are age- and sex-dependent. We determined z-scores for bone mineral mass, cortical thickness, and bone mineral density in the radius in various conditions and diseases in both sexes. In the males, z-scores were calculated for age, but in the females z-scores for menopausal status (years postmenopausal exclusive of years on estrogen treatment) were found to be more appropriate. With few exceptions, changes in a disease were of a similar order in both sexes. For bone mineral mass few mean z-scores were significantly increased, but diseases with significantly decreased mean z-scores were numerous. The usefulness of z-scores in diagnosis and study of metabolic bone disease is discussed.