Pediatric adrenal insufficiency: thirty years experience at a Portuguese hospital.

BACKGROUND: Adrenal insufficiency (AI) is a life-threatening condition caused by an impaired secretion of the adrenal glucocorticoid and mineralocorticoid hormones. It comprises a heterogeneous group of primary, secondary and acquired disorders. Presentation differs according to the child's age, but it usually presents with nonspecific and insidious symptoms and signs. The main purpose of this study was to describe and compare patients with primary or secondary AI. METHODS: Retrospective analysis of all patients with adrenal insufficiency followed at the Pediatric Endocrinology Unit in a tertiary care Portuguese hospital over the last 30 years. Data on family history, age at the first manifestation and at etiological diagnosis, and clinical presentation (symptoms, signs and laboratory evaluation) was gathered for all patients. RESULTS: Twenty-eight patients with AI were included; 67.9% were male, with a median (25th-75th percentile, P25-P75) age of 1 (0.5-36) month at the first presentation. The principal diagnostic categories were panhypopituitarism (42.9%) and congenital adrenal hyperplasia (25%). The most frequent manifestations (75%) were vomiting and weight loss. They were followed for a median (P25-P75) period of 3.5 (0.6-15.5) years. In respect to neurodevelopmental delay and learning difficulties, they were more common in the secondary AI group. CONCLUSIONS: Despite medical advances, the diagnosis and management of AI remains a challenge, particularly in the pediatric population, and clinicians must have a high index of suspicion. An early identification of AI can prevent a potential lethal outcome, which may result from severe cardiovascular and hemodynamic instability.

Acetabular version on magnetic resonance imaging: analysis of two different measuring techniques.

BACKGROUND: Both increased anteversion and retroversion of the acetabulum can lead to clinical problems. Although computed tomography (CT) is the gold standard in acetabular version imaging, magnetic resonance imaging (MRI) is becoming increasingly popular. We conducted this retrospective study to answer the following questions: 1) can the bony landmarks necessary to outline and measure acetabular version on MRI be consistently and reproducibly identified; 2) are soft-tissue (labral) landmarks comparable to bony landmarks for the measurement of acetabular version? METHODS: Twenty-nine MRI torsional profile examinations were studied. A total of 232 readings (116 each for right and left sided acetabulae) were involved. Acetabular anteversion angle (AAA) was measured using two different methods (i.e. bony acetabulum landmarks and labrum), by two investigators, at two separate times. RESULTS: Mean age was 13 years, 8 months with a range of 14 years. There were 12 male patients and 17 female. It was possible to consistently identify bony and labral landmarks in all MR images. AAA measurements using both methods were consistent and reproducible. When comparing the two methods to each other we found them to be in excellent agreement with an ICC of 0.943 (95% confidence interval, 0.927 to 0.956), 37% of all readings were in perfect agreement and 97% were within 5 degrees. The mean difference in measurement between methods was 1.34 degrees. CONCLUSION: Measurement of acetabular version using MRI remains consistent independent of the method used (bone versus labrum). MRI can provide adequate information for calculating acetabular version.

CT and MRI lower extremity torsional profile studies: measurement reproducibility.

BACKGROUND: Assessment of lower extremity (LE) torsional profile using computed tomography (CT) imaging is a well-recognized imaging method that supplements the clinical examination. Magnetic resonance imaging (MRI) is another advanced imaging modality that can be used as an alternative, since there are many growing concerns of radiation exposure with traditional CT studies, particularly in the skeletally immature population. METHODS: Sixty-two patients between the ages of 7 and 19 years were included. Thirty-four had CT and 28 had MRI for assessment of LE torsional profile. All patients had clinical evidence of torsional malalignment. CT and MR images were randomized and de-identified. Two observers measured femoral anteversion and tibial torsion based on previously published methodologies. This exercise was repeated 2 weeks later and the data were tabulated and statistical analysis was performed. Radiation exposure for the patients studied by CT was estimated. RESULTS: The mean age of the patients was 14.4 years (range 9.5-18.9 years) and 13.8 years (range 7.3-18.9 years) for the CT and MRI groups, respectively. Inter-observer reliability for both CT and MRI studies were excellent. The intra-class correlation coefficient (ICC) for femoral anteversion and tibial torsion studied by CT and MRI for both observers at both times were excellent. The radiation exposure for CT examination averaged 0.3-0.5 mSv, compared to none with the MRI method. CONCLUSIONS: MRI provides a reproducible method for assessing the torsional profile in children and adolescents using similar anatomic landmarks for measurements as those used on CT torsional profile. In circumstances where MRI methods are readily available (and affordable), the CT torsional profile can be replaced with MRI methods, in the current era of growing concerns of radiation hazards and increasing awareness about radiation safety. LEVEL OF EVIDENCE: Diagnostic Level III.