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R Lindsay

Publications and source records attributed to R Lindsay.

At least 73 records · Page 4Linked to original sources

Randomised controlled study of effect of parathyroid hormone on vertebral-bone mass and fracture incidence among postmenopausal women on oestrogen with osteoporosis.

BACKGROUND: Small increases in bone mass are commonly seen with existing treatments for osteoporosis, which reduce bone remodelling and primarily prevent bone loss. Since these drugs reduce but do not eliminate risk of fractures, an anabolic agent that would increase bone mass and potentially cure the underlying skeletal problem is needed. METHODS: We did a 3-year randomised controlled trial to find out the effects of 1-34 human parathyroid hormone (hPTH [1-34], 400 U/25 micrograms daily subcutaneously) in postmenopausal women with osteoporosis taking hormone-replacement therapy (n = 17). The controls were women taking hormone-replacement therapy only (n = 17). The primary outcome was bone-mineral density of the lumbar vertebrae, with bone-mineral density at other sites and vertebral fractures as secondary endpoints. FINDINGS: Patients taking hormone-replacement therapy and PTH (1-34) had continuous increase in vertebral bone-mineral density during the 3 years, whereas there was no significant change in the control group. The total increase in vertebral bone-mineral density was 13.0% (p < 0.001); 2.7% at the hip (p = 0.05); and 8.0% in total-body bone mineral (p = 0.002). No loss of bone mass was found at any skeletal site. Increased bone mass was associated with a reduction in the rate of vertebral fractures, which was significant when fractures were taken as a 15% reduction in vertebral height (p = 0.04). During the first 6 months of treatment, serum osteocalcin concentration, which reflects bone formation, increased by more than 55%, whereas excretion of crosslinked n-telopeptide, which reflects bone resorption, increased by only 20%, which suggests some uncoupling of bone formation and resorption. By 6 months, there were similar increases in both markers, which gradually returned towards baseline as the study progressed. Vertebral bone-mineral density increased most during the first year of PTH treatment. INTERPRETATION: We found that PTH has a pronouned anabolic effect on the central skeleton in patients on hormone-replacement therapy. PTH also increases total-body bone mineral, with no detrimental effects at any skeletal site. The increased vertebral mass was associated with a reduced rate of vertebral fracture, despite increased bone turnover. Bone-mass changes may be consistent with a reduction in all osteoporotic fractures. If confirmed in larger studies, these data have important implications for the treatment of postmenopausal osteoporosis.

Absorptiometry, Photon↗

Reduced bone mass and fat-free mass in women with multiple sclerosis: effects of ambulatory status and glucocorticoid Use.

Multiple sclerosis (MS) is associated with reduced bone mass and vitamin D deficiency. The underlying pathophysiology of the bone disease is uncertain, however, acute and long-term glucocorticoid use, progressive immobilization, vitamin D deficiency, and possibly skeletal muscle atrophy are likely to be determinants. The aims of this study were to determine (a) whether multiple sclerosis is associated with reduced fat-free mass and (b) whether in patients with multiple sclerosis, ambulation ability or glucocorticoid use is associated with bone mass and/or fat-free mass. Seventy-one female patients with MS were compared with 71 healthy, age-matched female controls. Total body bone mineral content (TBBMC, kg), fat mass (FM, kg), and fat-free mass (FFM, kg) were measured using dual X-ray absorptiometry. Disability status was graded according to the Kurtzke Expanded Disability Status Scale (EDSS) as ambulatory, with or without aide (EDSS score of 0 to 6.5), or predominantly wheelchair bound (EDSS score > 6.5). The patients with MS, when compared to age-comparable controls, had deficits in TBBMC ( approximately 8%, -0.3 +/- 0.1 SD, P < 0.04) and FFM ( approximately 5%, -0.3 +/- 0.1 SD, P < 0.01). Both TBBMC and FFM were negatively associated with EDSS score (r = 0.33, P < 0.01, and r = 0.41, P < 0.01, respectively). Patients with MS who were nonambulatory had even greater deficits in TBBMC and FFM as compared with age-matched controls (-0.6 +/- 0.1 SD, P < 0.01, and -0.6 +/- 0. 1 SD, P < 0.01, respectively). By contrast, as compared with age-comparable controls, ambulatory patients with MS had no deficits in bone mass or soft tissue mass. When compared with ambulatory patients with MS, nonambulatory patients with MS had deficits in TBBMC and FFM (P < 0.01 and P < 0.01, respectively). The difference in TBBMC was largely caused by the difference in fat-free mass, whereas the difference in FFM was largely caused by the difference in glucocorticoid use based on analysis of covariance. We conclude that in patients with multiple sclerosis, physical disuse is the main determinant for the reduction in bone mass. Glucocorticoid treatment is the major determinant of the reduction in fat-free mass and thus also contributes to the reduction in bone mass.

Adipose Tissue↗

Short-term immobilization-induced cancellous bone loss is limited to regions undergoing high turnover and/or modeling in mature rats.

Estrogen and calcium deficiencies increase both bone resorption and formation, whereas immobilization mainly decreases bone formation. How these functionally different risk factors for bone loss interact in cancellous bone undergoing modeling or remodeling activity is not well understood. Mature (6-month-old) female rats were subjected to sham operation (sham), ovariectomy (ovx), dietary calcium deficiency (LoCa, 0.1% Ca), and sciatic and femoral denervation (IM), ovx+IM, or LoCa+IM for 4 weeks. The primary spongiosa, the region of active modeling within 1 mm of the growth plate, in ovx, LoCa, and IM groups showed a decrease in cancellous bone volume, trabecular number, and connectivity when compared to sham controls. Groups combining two risk factors exhibited additive changes when compared with single risk factor groups. In the secondary spongiosa, an area with little modeling activity, ovx and LoCa groups, as expected, lost bone. In contrast with the primary spongiosa, IM alone did not induce bone loss in the secondary spongiosa, and the groups with a combination of IM and ovx or IM and LoCa showed a greater bone loss than either ovx or LoCa alone. Ovx and LoCa groups showed increases in both bone formation rate and eroded surface in the secondary spongiosa, while IM groups showed a decrease in bone formation rate. Combining IM with either ovx or LoCa resulted in increased eroded surface. The effects on cortical bone were assessed at the tibio-fibular junction. A trend toward decreased percentage of cortical bone area and an increase in marrow cavity area were observed in the combined deficiency groups only. These changes were the result of a statistically significant increase in endosteal eroded surface in IM+ovx and IM+LoCa groups. Our results demonstrate that immobilization-induced bone loss is restricted to the primary spongiosa where most modeling events occur. However, the inhibitory effect of IM on bone formation in the secondary spongiosa is unmasked in remodeling sites when a high turnover state is provided by either estrogen or dietary calcium deficiency. These results suggest that the presence of a risk factor, such as immobilization, which in the short-term causes inhibition of bone formation, does not predispose the skeleton to rapid cancellous bone loss except when accompanied by modeling or high turnover.

Animals↗

Prednisolone alone, or in combination with estrogen or dietary calcium deficiency or immobilization, inhibits bone formation but does not induce bone loss in mature rats.

Glucocorticoid use has long been recognized as a risk factor for bone loss, resulting in an increased fracture incidence in humans. However, steroid-treated patients often present with other complications that predispose to bone loss, such as immobilization, and little is known about the interaction of these other risk factors for bone loss and glucocorticoids. In the present study, mature female rats were treated with prednisolone (Pred) or vehicle, in combination with ovariectomy (ovx), dietary calcium deficiency (LoCa), or right hind limb immobilization (IM). After 4 weeks of treatment, the rats were killed and the right tibia and tibiofibular junction were collected for quantitative histomorphometric analysis and the right femur was collected for bone mineral density (BMD) and mechanical strength determinations. As expected, ovx, LoCa, and IM decreased BMD in the distal femur and cancellous bone volume (CnBV/TV) in the proximal tibia. All Pred-treated groups responded with increases of BMD and CnBV/TV, when compared to their respective non-Pred treated groups. Mechanical strength testing of the cancellous bone of the distal femur reflected the changes in BMD and CnBV/TV. No differences in trabecular plate thickness were noted in any of the treatment groups. The Pred group showed a significant reduction in longitudinal growth rate, as well as bone formation rate (BFR/BS), in the proximal tibia when compared with their respective control groups, the latter indicated by a decrease in both mineralizing surface and mineral apposition rate. Most notably, osteoclast surface and urinary free pyridinoline, a bone resorption marker, increased significantly with each of the three risk factors. Pred treatment inhibited these increases but it did not exert significant reductions when used by itself. At the tibiofibular junction, there were no measurable changes in either total bone or cortical bone area. Endocortical BFR/BS were increased by ovx or LoCa but each was lowered by Pred treatment. Periosteal BFR/BS were increased by ovx and IM, and Pred exerted significant inhibition by itself and in combination with other risk factors. We conclude, therefore, that unlike the effects observed in humans treated with glucocorticoid, treatment of rats with prednisolone not only does not result in bone loss but may exert a protective effect on the skeleton through the inhibition of bone resorption.

Amino Acids↗

Maternally reported fetal activity levels and developmental diagnoses.

Retrospective maternal report of fetal activity level was compared with developmental diagnosis in 608 consecutively referred children. Maternal history of fetal activity level was also obtained from 140 unmatched well children in a general pediatric clinic. Fetal hyperactivity was positively associated with a diagnosis of child hyperactivity, and fetal hypoactivity was positively associated with a diagnosis of mental retardation in the children. Maternal histories of fetal activity level in the control group weakened the strength of the association between fetal hyperactivity and child hyperactivity but did not affect the association between fetal hypoactivity and mental retardation in children.

Apgar Score↗

Insulin-like growth factor-I in men with idiopathic osteoporosis.

The etiology of osteoporosis in most men without a history of alcohol abuse, hypogonadism, or glucocorticoid excess is unknown. Several histomorphometric reports have demonstrated a reduction in indices of bone formation. We tested the hypothesis that the putative reduction in bone formation in men with idiopathic osteoporosis may be related to deficiencies in skeletal mechanisms that are mediated by insulin-like growth factor I (IGF-I). Twenty-four middle-aged men (50.5 +/- 1.9 yr) with severe idiopathic osteoporosis (mean lumbar spine T-score -3.5 +/- 0.16) were studied. The following biochemical indices were all normal: serum calcium, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, testosterone, osteocalcin, carboxyterminal propeptide of type I collagen, bone specific alkaline phosphatase, urinary calcium, and collagen crosslinks. Parathyroid hormone level was in the lower range of normal, 25 +/- 2 pg/mL (nl: 10-65). Mean serum IGF-I level was also in the lower range of normal, 157.9 +/- 7.6 ng/mL (normal age-matched range, 140-260 ng/mL). Eight men had IGF-I levels that were below 140 ng/mL. The mean IGF-IZ score was -0.75, significantly different from the expected mean of zero (P = 0.0002). IGF-I was correlated negatively with age (r = -0.49, P < 0.02). With age held constant, serum IGF-I accounted for 15% of the variance in lumbar bone mineral density (BMD; P < 0.001). The osteocalcin concentration correlated well with bone density at the distal 1/3 radius (r = +0.44; P < 0.002). Histomorphometric analysis of bone biopsy specimens showed significant reductions in cancellous bone volume (31%; P < 0.001), cortical width (28%; P < 0.05), osteoid surface (33%; P < 0.01), and bone formation rate (54%; P < 0.01) when results were compared with age-matched control subjects. Percent eroded surface was normal and was correlated inversely with serum IGF-I levels (r = -0.5; P < 0.04). These results suggest that serum IGF-I levels are reduced in men with idiopathic osteoporosis and that IGF-I correlates with and may contribute to the reduction in lumbar spine bone mass density (BMD). The low IGF-I levels may reflect the reduction in bone formation demonstrated by histomorphometry. Insights into the etiology of idiopathic osteoporosis in men may be revealed by further studies of the IGF-I axis.

Adult↗

Histomorphometric assessment of bone mass, structure, and remodeling: a comparison between healthy black and white premenopausal women.

While noninvasive studies of bone mass and turnover in blacks and whites abound, histologic evaluations are very rare. We have performed a comparative bone histomorphometric study of iliac biopsies from 55 healthy, premenopausal women including 21 blacks (mean age 33.4 + 1.2 years) and 34 whites (mean age 32.5 + 0.8 years) of comparable age, weight, body composition, education, and lifestyle. Biochemical indices of mineral metabolism: parathyroid hormone, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, serum ionized calcium, serum phosphorus, and urinary calcium/creatinine were measured in the fasting state. Blacks had lower 25-hydroxyvitamin D (315 +/- 3.36 vs. 63.21 +/- 3.79 nmol/l, p = 0.0001). Histomorphometric indices of bone volume, structure, and connectivity were not different between groups. The following indices of bone remodeling were also similar in both groups: eroded perimeter, osteoid width, mineralizing perimeter, tissue-based bone formation rate, osteoid maturation time, active formation period, and activation frequency. However, osteoid perimeter (black [B] = 15.85 +/- 1.30 vs. white [W] = 9.49 +/- 0.70%, p = 0.0002), osteoid area (B = 2.55 +/- 0.32 vs. W = 1.39 +/- 0.12%, p = 0.003), single-labeled perimeter (B = 5.46 +/- 0.54 vs. W = 4.04 +/- 0.33%, p = 0.03), mineralization lag time (B = 38.18 +/- 4.04 vs. W = 21.83 +/- 1.60 days, p < 0.009), and total formation period (B = 148.15 +/- 19.70 vs. W = 84.04 +/- 7.62 days, p = 0.0056) were higher in blacks than in whites. The quiescent perimeter (B = 76.91 +/- 1.40 vs. W = 84.25 +/- 0.91%, p = 0.0001), mineral apposition rate (B = 0.70 +/- 0.02 vs. W = 0.75 +/- 0.02 micron/day, p = 0.066), mineralizing osteoid perimeter (B = 0.49 +/- 0.04 vs. W = 0.75 +/- 0.04%, p = 0.0001) and adjusted apposition rate (B = 0.35 +/- 0.04 vs. W = 0.58 +/- 0.04 micron3/micron2/day, p = 0.0001) were all lower in blacks than in whites. These results indicate that there are no differences in bone volume, microstructure, or turnover between black and white premenopausal women. However, there are significant differences in the mechanism of bone formation between the two groups, with a lower rate of mineralized matrix apposition within each remodeling unit and a longer total formation period in blacks than in whites. The differences appear to the result of more frequent and/or longer inactive periods in the life span of the bone formation units in blacks. These differences may allow a greater overall deposition of bone mineral in black women and therefore help explain a higher bone mass and perhaps better bone quality in black than white women.

Adult↗

Resistance to bone resorbing effects of PTH in black women.

Black women have a lower incidence of vertebral and hip fractures than white women, possibly due to differences in skeletal and mineral metabolism. One suggested mechanism is that blacks have decreased skeletal sensitivity to parathyroid hormone (PTH). To test this hypothesis, we infused h(1-34)PTH in healthy premenopausal black (n = 15) and white (n = 18) women over 24 h and measured serum and urine indices of bone turnover and calcium metabolism throughout the infusion. At baseline, the mean 25-hydroxyvitamin D (25(OH)D) concentration was significantly lower in black women (46%). There were also nearly significant trends toward higher PTH and lower urinary calcium and pyridinoline levels in black women. During infusion, there were no racial differences in the mean (1-34)PTH levels achieved or in resultant elevations of serum calcium or 1,25-dihydroxyvitamin D (1,25(OH)2D) levels. Endogenous parathyroid suppression (measured by (1-84)PTH levels) was also similar between blacks and whites. There was an initial decline in urinary calcium/creatinine in both groups with a greater reduction in black women early in the infusion period (p < 0.05 at 8 h). Furthermore, blacks had lower levels of urinary calcium/creatinine throughout the infusion (p < 0.05 group difference). Bone formation markers (carboxy-terminal propeptide of type I procollagen and osteocalcin) decreased within 8 h and continued to decline throughout the infusion with no distinguishable racial differences (p < 0.05 time trend for both). The most dramatic difference between black and white women in response to PTH infusion was represented by the bone resorption markers. Three separate metabolites of bone resorption (cross-linked N-telopeptide of type I collagen, cross-linked C-telopeptide of type I collagen, and free pyridinoline) all showed substantially greater elevations in white (mean peak increments 399, 725, and 43%) compared with black women (mean peak increments 317, 369, and 17%) during the infusion (p < 0.05 group differences for all three variables). These data strongly suggest that blacks have decreased skeletal sensitivity to the acute resorptive effects of increased PTH. This finding indicates that calcium homeostasis may be accomplished in blacks (during times of relative calcium deficiency) by greater conservation of calcium from nonskeletal sources (most likely renal) with relative preservation of skeletal tissue. These differences in calcium economy could account, at least in part, for the increased bone mass and lower incidence of osteoporotic fractures in black women.

Adult↗

The systemic effect of intraarticular administration of corticosteroid on markers of bone formation and bone resorption in patients with rheumatoid arthritis.

OBJECTIVE: To assess the effects of intraarticular (IA) corticosteroid use on bone metabolism in patients with rheumatoid arthritis (RA). METHODS: Levels of the bone turnover markers, serum osteocalcin (BGP) and urinary pyridinoline (PYD), were monitored in RA patients for 4 weeks following a single IA administration of xylocaine alone or in combination with triamcinolone acetonide. RESULTS: Levels of the bone resorption marker, PYD, did not show any significant change, whereas BGP levels were drastically decreased 1 day after IA administration of corticosteroid, and then returned to pretreatment levels by day 14. The efficacy of IA corticosteroid treatment lasted for 4 weeks. CONCLUSION: Our results suggest that IA administration of corticosteroid has no net effects on bone resorption and only a transient systemic effect on bone formation. IA corticosteroid administration may be better for bone metabolism than continuous use of orally administered corticosteroid.

Aged↗

Temporal expression of the anabolic action of PTH in cancellous bone of ovariectomized rats.

When administered intermittently, parathyroid hormone (PTH) is a potent anabolic agent in both human and animal bone. To improve our understanding of this anabolic effect, we have examined the time course of PTH action in an established animal model of estrogen deficiency-induced bone loss: the ovariectomized rat. Animals were ovariectomized (Ovx) and allowed to lose bone for 6 weeks. A dose of 20 micrograms/kg/d of rat PTH (1-34) was administered s.c., 6 days each week for periods of 1, 2, 3, 4, 6 and 8 weeks. Animals were sacrificed for evaluation of skeletal histomorphometry of the proximal tibia and mechanical strength of the cancellous bone in the marrow cavity of the distal femur. Cancellous bone volume (Cn-BV/TV) increased gradually over 8 weeks of treatment (16.8 +/- 1.6 to 24.1 +/- 2.7%) as did the bone formation rate (0.308 +/- 0.054 to 1.659 +/- 0.293 microns3/micron2/d), as determined by an increase in both total mineralization surface (15.5 +/- 2.1 to 42.7 +/- 5.0%) and mineral apposition rate (1.88 +/- 0.20 to 3.55 +/- 0.39 microns/d). The largest increments in these variables reflecting bone formation occurred over the first week of treatment. This bone formation was accompanied by an increase in trabecular thickness (Tb.Th) (55.3 +/- 3.4 to 80.5 +/- 5.0 microns) without a corresponding increment in trabecular number (Tb.N) (3.65 +/- 0.17 to 3.55 +/- 0.26). Extensive tetracycline labels were visualized on the surface of trabecular rod-like and plate-like structures. A small transient, though not statistically significant, increase occurred in both eroded surface and urinary pyridinoline concentration immediately after the onset of PTH administration. Osteocalcin showed a small decrement in the first two weeks after PTH administration, but the levels were elevated when compared with the Ovx control in later weeks. Mechanical strength of the cancellous bone also increased significantly with PTH treatment (20.5 +/- 2.4 to 46.1 +/- 10.0 Newtons). Our results showed that: 1) intermittent PTH treatment of Ovx rats elicited an immediate increase of bone formation activity by the existing osteoblasts, 2) the increase of Cn-BV/TV after PTH administration resulted primarily from an increase in Tb.Th, and 3) improved mechanical strength after PTH treatment can be achieved by increases in Tb.Th without an increase in Tb.N.

Amino Acids↗

Bone density change and biochemical indices of skeletal turnover.

Although biochemical markers of skeletal turnover cannot replace bone density scanning for the diagnosis of osteoporosis, it is thought that they may help add to prediction of fracture risk and help determine adequacy of osteoporosis therapy. Nevertheless, whether biochemical markers in the serum or urine can predict individual rates of bone loss in the spine or hip region is unknown. We studied a heterogeneous group of women (n = 81) who were premenopausal, untreated postmenopausal, and estrogen-treated postmenopausal with baseline determination of body mass index (BMI), calcium intake, biochemical measurements, and serial bone densitometry over 3 years. Serum assays included bone Gla protein (BGP), total and bone-specific alkaline phosphatase (AP, BSAP), carboxyterminal propeptide of type I procollagen (PICP), carboxyterminal telopeptide of type I collagen (ICTP) and tartrate-resistant acid phosphatase (TRAP). Urine assays included hydroxyproline (OHP), calcium, total pyridinoline, and total deoxypyridinoline. Individual biochemical markers and calcium intake were modestly correlated with bone density changes but were inconsistent regarding the spine versus the hip. All of the formation variables were significantly correlated to spine density change (r = -0.24 to -0.49) whereas the only resorption variable that correlated was urine OHp/Cr (r = -0.31). The only formation variable that correlated with hip density change was serum PICP whereas all of the resorption variables except serum TRAP were correlated (r = -0.23 to -0.35). "High turnover" individuals were defined at those with levels of biochemical variables at least 1 SD above the mean young normal for each variable. Higher bone loss rates were seen in this group for several of the turnover markers compared with bone loss rates in all other individuals. However, the sensitivity of this "high turnover" status for identifying high bone losers did not exceed 60% for any of the variables. In untreated postmenopausal women, a model using urine OHp, serum ICTP, serum BSAP, and calcium intake was able to predict 42% of the variance of change in BMD of the lumbar spine. A model using BMI, serum ICTP, and serum BGP could predict 32% of the variance of change in BMD of the femoral neck. No combination of markers could predict variance in bone density change at either site in estrogenized women (premenopausal and estrogen-treated postmenopausal). We conclude that measuring individual serum and urine markers of bone turnover cannot accurately predict bone loss rates in the spine and hip; however, combinations of demographic and biochemical variables could predict some of the variance in untreated postmenopausal women. Biochemical markers cannot replace serial bone densitometry for accurate determination of change in bone mass at the most clinically relevant sites.

Adult↗

The menopause and osteoporosis.

Osteoporosis is a disease of reduced skeletal mass and microarchitectural deterioration of the skeleton, resulting in an increased risk of fractures. With the aging of the population, the considerable financial and personal costs of osteoporosis will increase. The loss of ovarian hormone production in menopause is the major risk factor for osteoporosis, causing increased skeletal resorption and relatively decreased bone formation. Estrogen administration protects from the loss of bone mass and reduces the incidence of vertebral and hip fractures, although administration must be continuous for the beneficial effects to remain. These effects occur regardless of the route of administration or the concomitant use of a progestin. Alternatives to estrogen are currently in development, including calcitonin, bisphosphonates, and tissue-specific estrogen.

Estrogen Replacement Therapy↗

Laboratory presentation in diabetic ketoacidosis and duration of therapy.

OBJECTIVE: To determine if initial emergency department (ED) laboratory parameters in children with diabetic ketoacidosis (DKA) can predict the minimum duration of continuous insulin therapy and aid in ED triage. DESIGN: Retrospective chart review, over a four-year period. SETTING: Tertiary care pediatric center ED. PATIENTS: All patients in DKA, managed with a standard hospital protocol were included. Standard therapy consisted of an intravenous infusion over an hour of normal saline or Ringer's lactate, followed by 0.45% saline (potassium acetate/ phosphate added) at 1.5 times maintenance and insulin infusion (0.1 units/kg/h). New-onset diabetic patients were excluded. MAIN RESULTS: One hundred thirty-two visits (45 patients, 55.5% female) were reviewed. Three of 60 (5%) patient-visits with moderate to severe DKA (serum pH < 7.20 and serum bicarbonate concentration < 10 mmol/L) had their acidosis corrected (serum pH > or = 7.30 or serum bicarbonate concentration > or = 15 mmol/L) within four hours compared to 33 of 72 (46%) patient-visits with mild DKA (serum pH > or = 7.20 or serum bicarbonate concentration > or = 10 mmol/L) (P < 0.0001). The acidosis was corrected within six hours in 69 and 11% of the mild and moderate-severe DKA group, respectively (P < 0.0001). CONCLUSIONS: Initial laboratory presentation can help predict the minimum necessary duration of therapy in pediatric patient with DKA, aid early triage decision in the ED, and select a subgroup of patients who may be considered for outpatient management.

Adolescent↗