Circulating glucocorticoid bioactivity during peroral glucocorticoid treatment in children and adolescents with inflammatory bowel disease

Screening for adrenal suppression in children with inflammatory bowel disease discontinuing glucocorticoid therapy

Background

Pharmacological doses of corticoids may result in adrenal suppression but with individual sensitivity. In paediatric inflammatory bowel disease (IBD), glucocorticoids are needed in the majority of the patients but there are less studies related to tapering off the drugs. The objective of this study was to estimate the frequency of adrenal insufficiency in children with IBD that were at the end of their systemic glucocorticoid therapy course.

Methods

The study was a retrospective case series of 59 consecutive paediatric IBD patients (median age 14.1 years; Crohn’s disease n = 22, ulcerative colitis n = 26, unclassified colitis n = 11) that were on oral prednisolone therapy about to be discontinued. The study patients were treated in a tertiary university hospital setting. Serum morning cortisol was measured with Immulite 2000 cortisol kit. Values < 20 nmol/l are undetectable and indicate adrenal suppression, values > 69 nmol/l are considered to represent normal basal secretion.

Results

The morning cortisol was below the reference range in 20% of the patients and undetectable in 10%. Low cortisol levels associated with higher daily glucocorticoid doses (median 7.2 mg/m² vs. 3.0 mg/m² in patients with normal cortisol levels, p < 0.05) and with the long duration of the treatment (median 11 months vs. 4 months, p < 0.05). Patients with undetectable cortisol levels recovered within few weeks (median 5.6 weeks).

Conclusions

In paediatric IBD prolonged courses of glucocorticoids are frequent due to the steroid-dependent nature of the disease in a considerable proportion of patients. Adrenal suppression may occur in at least one fifth of the patients despite slowly tapering off the glucocorticoids. Notably, this is based on a set of serum cortisol measurements by request of experienced clinicians. All paediatric IBD patients receiving conventional doses of oral glucocorticoids should be subjected to screening for adrenal suppression when anticipated discontinuation of the drug.

Soluble urokinase plasminogen activator receptor suPAR as a marker for inflammation in pediatric inflammatory bowel disease

OBJECTIVE

In inflammatory bowel disease (IBD), more means to monitor early therapeutic response are needed. In pediatric IBD, blood inflammatory markers erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) may be low in 10 to 20% of patients with severe disease. Recently, soluble urokinase plasminogen activator receptor (suPAR) was described as a potential blood inflammatory marker in adult IBD.

METHODS

We tested the performance of suPAR by the start of therapy with glucocorticoids (n = 19) or TNF-α-antagonist (n = 16) in pediatric IBD (Crohn's disease n = 19, ulcerative colitis (UC) n = 16).

RESULTS

The levels of suPAR were low in both patient groups studied. There was no difference in the values regarding the presence of Crohn's disease or ulcerative colitis. Thus, all analyses were performed on the entire sample set. Glucocorticoid therapy, however, resulted in a significant decline in suPAR levels from a median of 3.06 to 2.54 ng/ml (p < 0.01). In contrast, TNF-α-antagonist had no effect. The suPAR levels did not associate with ESR or CRP or fecal calprotectin (FC).

CONCLUSIONS

In pediatric IBD, the suPAR levels in blood are low and do not reflect the level of intestinal inflammation assessed with FC. The introduction of corticoids, however, results in a decline of suPAR levels in blood but not reflect therapeutic response to TNF-α-antagonist. Thus, suPAR is of limited value in assessing systemic inflammatory responses in pediatric IBD.

Glucocorticoid sensitivity in inflammatory bowel disease

Glucocorticoid therapy is used in the treatment of moderate to severe inflammatory bowel disease (IBD). However, IBD patients display varying degrees of glucocorticoid sensitivity: some respond rapidly to the given treatment, whereas others show no response, or develop steroid therapy-related side-effects. At present, we cannot foresee whether the patient will benefit from the administered glucocorticoids or not. During the past 10 years, numerous attempts have been made to provide the means to identify and predict steroid therapy-sensitive patients in advance. This would be vital to avoid unnecessary glucocorticoid exposure in patients that do not respond to treatment with steroids. Here we provide a concise review of recent developments regarding the molecular basis of glucocorticoid sensitivity in IBD patients and the methods employed to assess it.

High-sensitivity C-reactive protein in paediatric inflammatory bowel disease

AIM: To study whether high-sensitivity C-reactive protein (hs-CRP) measurement can aid the assessment of disease activity and glucocorticoid treatment in paediatric inflammatory bowel disease (IBD).

METHODS: CRP levels were measured in 39 children with IBD undergoing colonoscopy [median age 12.8 years, Crohn’s disease (CD) n = 20], in 22 other children with IBD followed for acute response to glucocorticoids, and in 33 paediatric non-IBD patients. When standard CRP level was below detection limit (< 5 mg/L), hs-CRP was analyzed.

RESULTS: Sixty-four percent (25/39) of the children with IBD undergoing colonoscopy displayed undetectable (< 5 mg/L) standard CRP levels. Of these, the hs-CRP measurement could not differentiate between active (median, 0.2 mg/L, range, 0.007-1.37, n = 17) or quiescent (0.1 mg/L, 0.01-1.89, n = 8, P = NS) disease. Patients with ileocolonic CD had higher CRP levels (14 mg/L, 0.06-45, n = 13) than patients with no ileal involvement (0.18 mg/L, 0.01-9, n = 7, P < 0.01) or ulcerative colitis (UC) (0.13 mg/L, 0.007-23, P < 0.05). In children with active IBD treated with systemic glucocorticoids, the standard CRP was undetectable in 59% of the patients. The hs-CRP levels did not differ between patients that responded to steroid therapy and in non-responders.

CONCLUSION: The measurement of hs-CRP did not prove useful in the assessment of disease activity or glucocorticoid treatment in paediatric IBD patients that had undetectable standard CRP.

New means to monitor the effect of glucocorticoid therapy in children

AIM: To study the individual effects of glucocorticoid (GC) therapy on the state of immune activation in patient serum.

METHODS: We developed a novel assay in which the effect of corticosteroid-treated patient serum on healthy donor peripheral blood mononuclear cells (target cells) was studied, with a panel of markers for effector [interferon (IFN)γ and interleukin (IL)-5] and regulatory T cells (FOXP3 and glucocorticoid-induced tumor necrosis factor receptor, GITR). The study group comprised 19 children with inflammatory bowel disease. The individual effect of patient serum on target cells was analyzed prior to GC therapy and 2 wk later.

RESULTS: The effect of GC therapy mediated by patient serum was seen as a decrease in the target cells expression of regulatory T-cell-related markers GITR (median suppression 24%, range of suppression 1%-63%, in 2 cases increase of 6% and 77%, P < 0.01 for mitogen-activated target cells) and FOXP3 (median suppression 33%, range of suppression 0%-79%, in one case an increase of 173%, P < 0.05 for resting cells), and secretion of IFNγ [from a mean of 87 700 pg/mL (SD 33 900 pg/mL) to 60 900 pg/mL (SD 44 200 pg/mL) in mitogen-activated target cells, 13 of the cases showed a decrease, P < 0.01]. The total or weight-related prednisolone dose did not correlate with the patient-serum-induced changes in the target cell markers.

CONCLUSION: GC response could be monitored at an individual level by studying the effect of patient serum on signaling pathways of target immune cells.

Glucocorticoid bioactivity does not predict response to steroid therapy in severe pediatric ulcerative colitis

BACKGROUND

The pathophysiological basis for corticosteroid (CS) failure in ulcerative colitis (UC) is unknown. A transactivation glucocorticoid bioassay (GBA) was developed to measure the biological activity of CS by quantifying glucocorticoid response elements. This approach eliminates differences in bioavailability, chemistry, affinity, and other potential differences between the various steroids regarding their ability to activate the glucocorticoid receptor. In this multicenter prospective study, we aimed to evaluate whether CS bioavailability plays a role in CS refractoriness in severe pediatric UC.

METHODS

GBA (using COS-1 transfected cells) was measured in the serum of 50 children (52% males, age 13.4 +/- 3.5 years) admitted for acute severe UC on the third day of CS treatment. Demographic, clinical, and laboratory data were prospectively recorded.

RESULTS

Of the children enrolled, 16 (32%) failed CS therapy and required infliximab (n = 14) or colectomy (n = 2) within a median of 10 days (interquartile range [IQR] 6.5-14.5). Reflecting internal validity of the assay, GBA was highly correlated with the last CS dose and the time interval to bloodletting (r = -0.41 and r = -0.54, respectively; P < 0.001). There was no statistically significant difference in the GBA levels between responders and nonresponders (249 nM versus 200 nM cortisol equivalent, P = 0.18). In a multivariate regression model adjusted for time elapsed from CS and the administered dose, GBA did not predict response to CS (P = 0.34).

CONCLUSIONS

The lack of correlation of GBA level and treatment outcome lends support to the hypothesis that the bioavailability, type, and dosing of intravenous CS are not associated with response or failure to the drug.

Adrenal cortisol secretion capacity in children and adolescents with new-onset, mild Crohn's disease

OBJECTIVES

To evaluate the integrity of the hypothalamic-pituitary-adrenal axis in active Crohn's disease (CD) among children and adolescents.

STUDY DESIGN

We retrieved data on patients with CD who participated in a prospective study where budesonide treatment was evaluated. Basal and adrenocorticotropic hormone and corticotropin-stimulated cortisol levels in 52 children and adolescents with CD were compared with levels obtained in 52 age-matched control subjects. Correlations of cortisol levels with pediatric CD activity index and C-reactive protein (CRP) as an inflammatory marker were also assessed.

RESULTS

Both basal and stimulated cortisol levels in CD were significantly higher than in control subjects: 364 +/- 173 versus 290 +/- 122 nmol/L (P = .029) and 865 +/- 236 versus 738 +/- 148 nmol/L (P < or = .001), respectively. Cortisol levels were correlated with CRP but not with pediatric CD activity index. Unlike in the control group, stimulated cortisol levels in patients with CD were not correlated with basal levels but rather with CRP (positive correlation) and age at diagnosis (negative correlation).

CONCLUSIONS

Contrary to previous reports suggesting that dysregulation of the hypothalamic-pituitary-adrenal axis is implicated in the susceptibility to and severity of CD and other chronic inflammatory diseases, we demonstrated an adequate response of this axis in pediatric CD, in proportion to the inflammation severity.

Circulating adiponectin as a marker for glucocorticoid-related side effects in children and adolescents with inflammatory bowel disease

Glucocorticoid therapy is widely used in clinical practice. However, treatment with steroids carries the risk of side effects. We investigated changes in serum adiponectin and leptin in response to systemic glucocorticoid treatment in 18 pediatric patients with inflammatory bowel disease and contrasted these findings to circulating glucocorticoid bioactivity measured with a mammalian cell bioassay. Interestingly, serum adiponectin levels at 2 to 4 weeks of therapy were significantly higher in patients who experienced acute glucocorticoid-related side effects (22.9 +/- 2.6 microg/mL, n = 7) than in those who did not (16.0 +/- 2.1 microg/mL, n = 11, P < 0.05). Serum leptin was not associated with side effects. Circulating adiponectin may serve as an early and readily available endogenous biomarker for acute glucocorticoid-related side effects in pediatric patients.