Patricia M. Crofton

Anti-Müllerian Hormone Is a Marker of Gonadotoxicity in Pre- and Postpubertal Girls Treated for Cancer: A Prospective Study

CONTEXT Cytotoxic treatment may accelerate depletion of the primordial follicle pool, leading to impaired fertility and premature menopause. Assessment of ovarian damage in prepubertal girls is not currently possible, but Anti-Müllerian Hormone (AMH) is a useful marker of ovarian reserve in adults. OBJECTIVE The objective of the study was to prospectively evaluate AMH measurement in children as a marker of ovarian toxicity during cancer treatment. DESIGN AND SETTING This was a prospective, longitudinal study at a University Hospital. PATIENTS Twenty-two females (17 prepubertal), median age 4.4 yr (range 0.3-15 yr), were recruited before treatment for cancer. MAIN OUTCOME MEASURES AMH, inhibin B, and FSH at diagnosis, after each chemotherapy course and during follow-up, were measured. Risk of gonadotoxicity was classified as low/medium (n = 13) or high (n = 9) based on chemotherapy agent, cumulative dose, and radiotherapy involving the ovaries. RESULTS Pretreatment AMH was detectable across the age range studied. AMH decreased progressively during chemotherapy (P < 0.0001) in both prepubertal and pubertal girls, becoming undetectable in 50% of patients, with recovery in the low/medium risk groups after completion of treatment. In the high-risk group, AMH became undetectable in all patients and showed no recovery. Inhibin B was undetectable in most patients before treatment and, with FSH, showed no clear relationship to treatment. CONCLUSION AMH is detectable in girls of all ages and falls rapidly during cancer treatment in both prepubertal and pubertal girls. Both the fall during treatment and recovery thereafter varied with risk of gonadotoxicity. AMH is therefore a clinically useful marker of damage to the ovarian reserve in girls receiving treatment for cancer.

Changes in dimeric inhibin A and B during normal early puberty in boys and girls

OBJECTIVE Although recently developed specific and sensitive assays of bioactive dimeric inhibin A and B have given new insights into the pituitary‐gonadal axis in adult men and during the adult female menstrual cycle, there have been no reports on circulating inhibin A and B during normal human puberty. The aim of this study was to assess the relationship of dimeric inhibin A and B to pubertal stage, FSH and testosterone or oestradiol in late prepuberty and in early puberty.

Bone Turnover and Growth During and After Continuing Chemotherapy in Children with Acute Lymphoblastic Leukemia

Children treated for acute lymphoblastic leukemia may develop reduced bone mineral density during treatment, but there is little information on the mechanisms involved. In a prospective, longitudinal study on 15 children with ALL, we undertook serial measurements of markers of bone and collagen turnover, insulin-like growth factor (IGF)-I and its binding proteins (IGFBPs)-3 and -2 during the second year of continuing chemotherapy. In eight patients we also measured lower leg length by knemometry. Height SD scores, lower leg length velocity, IGF-I, and markers of bone collagen turnover did not differ significantly from healthy children. However, bone alkaline phosphatase, a marker of the differentiated osteoblast, was lower (mean SD score, −0.64;p < 0.0001), whereas procollagen type III N-terminal propeptide (P3NP, a marker of soft tissue collagen turnover; mean SD score, +0.93, p < 0.05), IGFBP-3 (mean SD score, +0.76;p < 0.01), and IGFBP-2 (mean SD score, +1.24, p = 0.01) were all higher than in healthy children. IGFBP-3 decreased during episodes of afebrile neutropenia (p < 0.05). Within 3 mo after completion of treatment, bone ALP increased in all eight patients, but collagen markers showed little change. IGFBP-2 returned to normal posttreatment, but P3NP and IGFBP-3 remained significantly elevated compared with healthy children (mean SD scores, +1.51 and +1.36, respectively;p < 0.01). We conclude that continuing chemotherapy was associated with normal growth and bone collagen turnover but enhanced soft tissue collagen turnover. Bone bone alkaline phosphatase was low throughout treatment, which suggests impaired osteoblast differentiation resulting from a direct effect of chemotherapy on bone. Although the effect was reversible, the long-term implications for bone health in survivors remain uncertain.

Bone and collagen markers in preterm infants: relationship with growth and bone mineral content over the first 10 weeks of life.

In a longitudinal study of 25 preterm infants, we have examined the relationship of bone-specific alkaline phosphatase (ALP), C-terminal propeptide of type I collagen (PICP), N-terminal propeptide of type III procollagen (P3NP), C-terminal telopeptide of type I collagen, urinary pyridinoline (Pyd) and deoxypyridinoline (Dpd), with rates of gain in weight, length, and lower leg length and with bone mineral content (BMC), all measured at weekly intervals over the first 10 wk of life. Concentrations of all collagen markers were 10-fold higher than in older children. Each marker showed a distinctive pattern of postnatal change, with early increases in PICP and P3NP and decreases in ICTP reflecting postnatal growth. Once markers had reached a plateau during weeks 4–10, P3NP was positively correlated, whereas Pyd and Dpd were negatively correlated with rate of weight gain (r= +0.44, −0.46, and −0.40, respectively, p< 0.05). P3NP was also positively correlated with overall linear growth (r= +0.44, p< 0.05). PICP was strongly correlated with mean BMC (r= +0.63, p< 0.01) and with total BMC attained by the end of the study period (r= +0.81, p< 0.001). Bone ALP was positively correlated with the rate of bone mineral accretion (r= +0.55, p= 0.01). We conclude that the marker of soft-tissue collagen formation, P3NP, is a good marker for overall ponderal and linear growth in preterm infants, whereas the markers of collagen breakdown, Pyd and Dpd, have inverse relationships with weight gain. The osteoblast markers, PICP and bone ALP, seem to be good surrogate markers for bone mineralization in preterm infants. Markers may provide information on whole-body turnover of bone and collagen that is complementary to traditional physical measures of growth and bone mineralization.

Hydroxybutyrate near-patient testing to evaluate a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis in children

Background:  The aim of this study was to assess the clinical application of a near‐patient testing (NPT) device for capillary blood hydroxybutyrate (HOB) measurement in evaluating a new end‐point for intravenous insulin therapy in the treatment of diabetic ketoacidosis (DKA) in children.

Does ifosfamide affect gonadal function

Gonadal dysfunction and infertility are potential late effects of cancer therapy. Ifosfamide, an alkylating agent structurally related to cyclophosphamide, is thought to cause gonadal dysfunction, though there is little published evidence.

Evaluation of pituitary function after traumatic brain injury in childhood

Objectives  Post‐traumatic hypopituitarism is well described amongst adult traumatic brain injury (TBI) survivors. We aimed to determine the prevalence and clinical significance of pituitary dysfunction after head injury in childhood.

Bone alkaline phosphatase and collagen markers as early predictors of height velocity response to growth-promoting treatments in short normal children

OBJECTIVE A number of long‐term research studies are in progress to evaluate the effects of treatment with GH on growth and final height in children with short stature but no demonstrable abnormality of GH secretion. Such treatment is invasive, expensive and carries some risk to the child. An early indication of growth response would allow restriction of treatment to those children most likely to benefit, but anthropometric measurements are relatively subjective, insensitive and imprecise. The aim of this study was to evaluate bone alkaline phosphatase, procollagen Type I C‐terminal propeptide, procollagen Type III N‐terminal propeptide and the cross‐linked carboxyterminal telopeptide of Type I collagen as early biochemical predictors of height velocity response to growth‐promoting treatments in short normal children.

Effects of Dexamethasone Treatment on Bone and Collagen Turnover in Preterm Infants with Chronic Lung Disease

Dexamethasone is used commonly in the treatment of chronic lung disease of prematurity, but there are concerns about possible deleterious effects on growth and bone. Our aim in this study was to examine the effects of dexamethasone treatment on bone and collagen turnover in preterm infants. Bone-specific alkaline phosphatase, the C-terminal propeptide of type I collagen (PICP, reflecting whole-body type I collagen synthesis), and the N-terminal propeptide of type III procollagen (P3NP, reflecting soft tissue collagen turnover), together with the C-terminal telopeptide of type I collagen (ICTP), urinary pyridinoline (Pyd), and deoxypyridinoline (all markers of collagen breakdown) were measured at weekly intervals over the first 12 wk of life in 14 preterm infants with chronic lung disease treated with dexamethasone. Results were expressed as SD scores relative to preterm control infants not treated with dexamethasone. PICP, P3NP, ICTP, and Pyd all showed marked decreases (−2.1 to −3.7 SD scores) during the first week of treatment (p < 0.001), returning to pretreatment levels after stopping dexamethasone. In the group as a whole, these collagen markers were negatively correlated with dexamethasone dose (p < 0.0001); negative correlations were also seen in most individual babies, although the slopes of individual regression lines varied by a factor of 2. Weight gain at 12 wk was correlated with PICP, expressed as the mean SD score over 12 wk for each baby, (r = 0.69, p < 0.01) but not with other markers or cumulative dose of dexamethasone. We conclude that dexamethasone markedly suppressed collagen turnover in preterm infants in a dose-dependent fashion, although some babies were more affected than others. The degree of suppression of type I collagen synthesis was a strong independent predictor of overall weight gain over the first 12 wk of life.

Evaluation of salt supplementation in CF infants

BACKGROUND CF infants may be at increased risk of sodium depletion which may lead to impaired growth. The objective of this study was to evaluate their sodium supplementation requirements. METHODS Ten CF infants had serial measurements of weight and plasma/urine sodium and creatinine. Sodium supplementation was adjusted with the aim of maintaining fractional excretion (FENa) between 0.5% and 1.5% and urinary sodium > 10 mmol/L. RESULTS Urine sodium:creatinine (UNa:Cr) ratio strongly correlated with FENa [UNa:Cr (mmol/mmol)=35.0 x FENa (r=0.99)]. The FENa target range corresponded to UNa:Cr 17-52 mmol/mmol. All infants required sodium supplementation to achieve UNa:Cr > 17 mmol/mmol. Sodium supplement requirements (mean+/-SD) at ages 0-3, 3-6, 6-9 and 9-12 months were 1.9+/-0.5, 1.8+/-0.8, 1.9+/-0.9 and 0.8+/-0.4 mmol/kg/d. No infant required calorie supplementation to achieve expected weight gain. CONCLUSIONS Using current UK guidelines, many cases of sodium depletion may be overlooked. Some infants require more than the recommended 1-2 mmol/kg/d. UNa:Cr ratio is a useful non-invasive measure to monitor sodium supplementation.