Modulation de l’axe hypothalamo-hypophyso-surrénalien par l’utilisation des agents hypnotiques dans le contexte chirurgical

During stress, the relationship between the central nervous system and the immune system is essential to maintain homeostasis. The main neuroendocrine system involved in this interaction is the hypothalamic-pituitary-adrenal axis (HPA), which via the synthesis of glucocorticoids will modulate the intensity of the inflammatory response. Anaesthetic agents could be interacting with the HPA axis during surgery. Although etomidate currently remains in the center of the discussions, it seems, at least experimentally, that most hypnotics have the capacity to modulate the synthesis of adrenal steroids. Nevertheless, with the large literature on this subject, etomidate seems to be the most deleterious hypnotic agent on the HPA axis function. Its use should be limited when HPA axis is already altered.     

PATHOLOGICAL CASE OF THE MONTH: SUDDEN DEATH IN A CHILD AS A RESULT OF PANCREATITIS DURING VALPROIC ACID THERAPY

Valproic acid is a widely used drug in the treatment of epilepsy and, compared to other anticonvulsant drugs, is considered safe. The most common side effects of valproic acid ingestion or therapy are transient nausea, vomiting, abdominal cramps, and diarrhea. Most of these complaints are mild. However, more serious adverse reactions can occur such as hepatotoxicity and pancreatitis. It has been proposed that, whenever possible, valproic acid not be used in the younger child, the child with a severe seizure disorder or other neurological disorders, mental retardation, developmental delay, organic brain disease, congenital abnormalities, or the child who is taking multiple anticonvulsant drugs, as these factors may increase the likelihood of hepatotoxicity and/or pancreatitis. In the present report, we describe a fatal case of acute hemorrhagic pancreatitis in a four and a half-year-old Hispanic female child who was receiving valproic acid in combination with another anticonvulsant drug for control of focal seizures. The patient also received the macrolide antibiotic azithromycin. For pediatricians and forensic pathologists valproic acid-induced pancreatitis can be a challenging diagnosis which must not be mistaken for abdominal trauma. We discuss the workup of the patient and differential diagnosis.     

Small pituitary size in children with Fanconi anemia

BACKGROUND: Fanconi anemia (FA) is a genetic disorder associated with multiple congenital anomalies, bone marrow failure, and pituitary hypofunction including hypogonadism, thyroid dysfunction, and growth hormone (GH) deficiency. PROCEDURE: Among 44 patients with FA referred to Cincinnati Children's Hospital Medical Center (CCHMC) between 1975 and 2005, 33 had neuroimaging studies, including 11 cranial magnetic resonance imaging (MRIs). Two separate measurements per patient from these MRIs were used to evaluate pituitary height compared to on-site control data of similar measurements of cranial MRIs on 22 age and gender-matched children without any pathology involving the hypothalamic-pituitary system. Growth pattern and endocrine studies were reviewed to assess potential correlation with pituitary size. RESULTS: When compared to the age-gender matched on-site control sample, the mean pituitary height of FA patients was significantly smaller (P < 0.0001; mean +/- SE from mixed effects model with age and gender as covariates: 3.96 +/- 0.32 vs. 5.76 +/- 0.24). Upon further adjusting for the effect of the small head size by including bi-parietal diameter (BPD) as a covariate, the difference remained statistically significant (P = 0.0013). Findings on the growth pattern and endocrinological measurements are as follows: 50% of patients with small pituitary gland were short. GH and adrenal function tests were normal in all tested patients. Thyroid, pubertal status, and glucose regulation were abnormal in 30, 50, and 75% of patients tested. CONCLUSIONS: Children with FA tend to have unsuspected small pituitary glands beyond what is expected from the effects of their stunted growth. Further studies are required to reveal the clinical implications of this finding.     

Imaging of pediatric thyroid tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Pediatric thyroid cancer is rare in children; however, incidence is increasing. Papillary thyroid cancer and follicular thyroid cancer are the most common subtypes, comprising about 90% and 10% of cases, respectively. This paper provides consensus imaging recommendations for evaluation of pediatric patients with thyroid cancer at diagnosis and during follow-up.     

Impact of diagnostic and end-of-induction Curie scores with tandem high-dose chemotherapy and autologous transplants for metastatic high-risk neuroblastoma: A report from the Children's Oncology Group

Background

Diagnostic mIBG (meta-iodobenzylguanidine) scans are an integral component of response assessment in children with high-risk neuroblastoma. The role of end-of-induction (EOI) Curie scores (CS) was previously described in patients undergoing a single course of high-dose chemotherapy (HDC) and autologous hematopoietic cell transplant (AHCT) as consolidation therapy.

Objective

We now examine the prognostic significance of CS in patients randomized to tandem HDC and AHCT on the Children's Oncology Group (COG) trial ANBL0532.

Study design

A retrospective analysis of mIBG scans obtained from patients enrolled in COG ANBL0532 was performed. Evaluable patients had mIBG-avid, International Neuroblastoma Staging System (INSS) stage 4 disease, did not progress during induction therapy, consented to consolidation randomization, and received either single or tandem HDC (n = 80). Optimal CS cut points maximized the outcome difference (≤CS vs. >CS cut-off) according to the Youden index.

Results

For recipients of tandem HDC, the optimal cut point at diagnosis was CS = 12, with superior event-free survival (EFS) from study enrollment for patients with CS ≤ 12 (3-year EFS 74.2% ± 7.9%) versus CS > 12 (59.2% ± 7.1%) (p = .002). At EOI, the optimal cut point was CS = 0, with superior EOI EFS for patients with CS = 0 (72.9% ± 6.4%) versus CS > 0 (46.5% ± 9.1%) (p = .002).

Conclusion

In the setting of tandem transplantation for children with high-risk neuroblastoma, CS at diagnosis and EOI may identify a more favorable patient group. Patients treated with tandem HDC who exhibited a CS ≤ 12 at diagnosis or CS = 0 at EOI had superior EFS compared to those with CS above these cut points.     

Gastrointestinal pathology in neonates: new imaging strategies

The mainstay of imaging of gastrointestinal (GI) pathology in infants has always been and still is the plain radiograph of the abdomen and conventional contrast studies. In this review emphasis is placed on the situations where there are new imaging strategies and alternative modalities of imaging, including US, CT, MRI and radionuclide studies. This review will deal with GI pathology in the newborn and in the older neonate. It will also refer to any new approaches to imaging GI pathology in the premature infant. Finally the review will address how antenatal diagnosis of gastrointestinal tract abnormalities has changed the imaging strategy and management of the neonate.