P450 oxidoreductase deficiency - a new form of congenital adrenal hyperplasia

Patients with adrenal insufficiency, genital anomalies and bony malformations resembling the Antley- Bixler syndrome (a craniosynostosis syndrome), are likely to have P450 oxidoreductase (POR) deficiency. Since our first report in 2004, about 26 recessive POR mutations have been identified in 50 patients. POR is the obligate electron donor to all microsomal (type II) P450 enzymes, including the steroidogenic enzymes CYP17A1, CYP21A2 and CYP19A1. POR deficiency may cause disordered sexual development manifested as genital undervirilization in 46,XY newborns as well as overvirilization in those who are 46,XX. This may be explained by impaired aromatization of fetal androgens which may also lead to maternal virilization and low urinary estriol levels during pregnancy. A role for the alternate 'backdoor' pathway of androgen biosynthesis, leading to dihydrotestosterone production bypassing androstenedione and testosterone, has been suggested in POR deficiency but remains unclear. POR variants may play an important role in drug metabolism, as most drugs are metabolized by hepatic microsomal P450 enzymes. However, functional assays studying the effects of specific POR mutations on steroidogenesis showed that several POR variants impaired CYP17A1, CYP21A2 and CYP19A1 activities to different degrees, indicating that each POR variant must be studied separately for each potential target P450 enzyme. Thus, the impact of POR mutations on drug metabolism by hepatic P450s requires further investigation.

Randomized controlled trial on single dose steroid before thyroidectomy for benign disease to improve postoperative nausea, pain, and vocal function

OBJECTIVE: To evaluate the effects of a single preoperative dose of steroid on thyroidectomy outcomes. BACKGROUND: Nausea, pain, and voice alteration frequently occur after thyroidectomy. Because steroids effectively reduce nausea and inflammation, a preoperative administration of steroids could improve these thyroidectomy outcomes. METHODS: Seventy-two patients (men = 20, women = 52) undergoing thyroidectomy for benign disease were included in this randomized, controlled, 2 armed (group D: 8 mg dexamethasone, n = 37; group C: 0.9% NaCl, n = 35), double-blinded study (clinical trial number NCT00619086). Anesthesia, surgical procedures, antiemetics, and analgesic treatments were standardized. Nausea (0-3), pain (visual analog scale), antiemetic and analgesic requirements, and digital voice recording were documented before and 4, 8, 16, 24, 36, and 48 hours after surgery. Patients were followed-up 30 days after hospital discharge. RESULTS: Baseline characteristics were similar among the 2 treatment groups. Nausea was pronounced in the first 16 hours postoperatively (scores were <0.3 and 0.8-1.0 for group D and C, respectively (P = 0.005)), and was significantly lower in group D compared with group C during the observation period (P = 0.001). Pain diminished within 48 hours after surgery (visual analog scale 20 and 35 in group D and C, respectively (P = 0.009)). Antiemetic and analgesic requirements were also significantly diminished. Changes in voice mean frequency were less prominent in the dexamethasone group compared with the placebo group (P = 0.015). No steroid-related complications occurred. CONCLUSION: A preoperative single dose of steroid significantly reduced nausea, vomiting, and pain, and improved postoperative voice function within the first 48 hours (most pronounced within 16 hours) after thyroid resection; this strategy should be routinely applied in thyroidectomies.

High-resolution ultrasound confirms reduced synovial hyperplasia following rituximab treatment in rheumatoid arthritis

OBJECTIVE: To assess the response of RA patients to rituximab (RTX) treatment using a sensitive imaging technique for synovitis. METHODS: Twenty-three RA patients were treated with two 1000-mg infusions of the B-cell depleting antibody, RTX, in an observational protocol. Clinical response was assessed by the European League Against Rheumatism (EULAR) response criteria. High-resolution grey-scale and colour-coded power Doppler (PD) ultrasonography was performed at baseline and 6 months after RTX. The second to fifth MCP and PIP joints were bilaterally examined with joints in a neutral 0 position from a palmar view and scored from 0 to 3. RESULTS: Median disease activity score (DAS28) improved from 5.03 to 3.56 (P = 0.001), which corresponded to a EULAR moderate response in 11 of 23 patients and a EULAR good response in another 6 patients. Improved control of disease activity by RTX was also indicated by tapering of median daily corticosteroid doses from 10 to 5 mg, without flare ups. Mean grey-scale scores correlated with the swollen joint count at baseline (r = 0.484, P = 0.022) and month 6 (r = 0.519, P = 0.011). Mean grey-scale scores improved upon RTX from a 0.90 median (range 0.13-1.87) to 0.75 (range 0.19-1.50, P = 0.023). Frequency of PD positive joints was low (6.1%) at baseline and did not significantly change following RTX treatment. CONCLUSIONS: High-resolution grey-scale ultrasonography (US) examination confirmed reduced synovial hyperplasia, but the applied PD method displayed no significant changes. Therefore, only grey-scale US is recommended in follow-up examinations after RTX treatment.

Prostate specific antigen doubling time as auxiliary end point in hormone refractory prostatic carcinoma

In hormone refractory prostatic carcinoma (HRPCa), the majority of patients have bone metastases only, which are by definition non-measurable. This makes objective evaluation of chemotherapeutic agents difficult. Prostate specific antigen (PSA) as a dynamic model was analyzed as potential auxiliary end point in HRPCa.

A rare case of a large spinal meningioma with mediastinal extension and malignant behavior classified histologically as benign

AIM To report a rare case of a spinal WHO grade I meningioma extending through intervertebral foramina C7 to D4 with an extensive mediastinal mass and infiltration of the vertebrae, and to discuss the malignant behavior of a tumor classified as benign. METHODS (Clinical Presentation, Histology, and Imaging): A 54-year-old man suffered from increasing lower back pain with gait difficulties, weakness and numbness of the lower extremities, as well as urge incontinence. CT scan of the thorax and MRI scan of the spine revealed a large prevertebral tumor, which extended to the spinal canal and caused compression of the spinal cord at the levels of C7 to D4 leading to myelopathy with hyperintense signal alteration on T2-weighted MRI images. The signal constellation (T1 with and without contrast, T2, TIR) was highly suspicious for infiltration of vertebrae C7 to D5. Somatostatin receptor SPECT/CT with (111)In-DTPA-D: -Phe-1-octreotide detected a somatostatin receptor-positive mediastinal tumor with infiltration of multiple vertebrae, dura, and intervertebral foramina C7-D4, partially with Krenning score >2. Percutaneous biopsies of the mediastinal mass led to histopathological findings of WHO grade I meningioma of meningothelial subtype. RESULTS (Therapy): C7 to D4 laminoplasty was performed, and the intraspinal, extradural part of the tumor was microsurgically removed. Postoperative stereotactic radiation therapy was done using the volumetric modulated arc therapy (VMAT) technique (RapidArc). No PRRNT with (90)Y-DOTA-TOC was done. CONCLUSIONS Due to the rare incidence and complex presentation of this disease not amenable to complete surgical resection, an individualized treatment approach should be worked out interdisciplinarily. The treatment approach should be based not only on histology but also on clinical and imaging findings. Close clinical and radiological follow-up may be mandatory even for benign tumors.

STAR splicing mutations cause the severe phenotype of lipoid congenital adrenal hyperplasia: insights from a novel splice mutation and review of reported cases

OBJECTIVE The steroidogenic acute regulatory protein (StAR) transports cholesterol to the mitochondria for steroidogenesis. Loss of StAR function causes lipoid congenital adrenal hyperplasia (LCAH) which is characterized by impaired synthesis of adrenal and gonadal steroids causing adrenal insufficiency, 46,XY disorder of sex development (DSD) and failure of pubertal development. Partial loss of StAR activity may cause adrenal insufficiency only. PATIENT A newborn girl was admitted for mild dehydration, hyponatremia, hyperkalemia and hypoglycaemia and had normal external female genitalia without hyperpigmentation. Plasma cortisol, 17OH-progesterone, DHEA-S, androstendione and aldosterone were low, while ACTH and plasma renin activity were elevated, consistent with the diagnosis of primary adrenal insufficiency. Imaging showed normal adrenals, and cytogenetics revealed a 46,XX karyotype. She was treated with fluids, hydrocortisone and fludrocortisone. DESIGN, METHODS AND RESULTS Genetic studies revealed a novel homozygous STAR mutation in the 3' acceptor splice site of intron 4, c.466-1G>A (IVS4-1G>A). To test whether this mutation would affect splicing, we performed a minigene experiment with a plasmid construct containing wild-type or mutant StAR gDNA of exons-introns 4-6 in COS-1 cells. The splicing was assessed on total RNA using RT-PCR for STAR cDNAs. The mutant STAR minigene skipped exon 5 completely and changed the reading frame. Thus, it is predicted to produce an aberrant and shorter protein (p.V156GfsX19). Computational analysis revealed that this mutant protein lacks wild-type exons 5-7 which are essential for StAR-cholesterol interaction. CONCLUSIONS STAR c.466-1A skips exon 5 and causes a dramatic change in the C-terminal sequence of the protein, which is essential for StAR-cholesterol interaction. This splicing mutation is a loss-of-function mutation explaining the severe phenotype of our patient. Thus far, all reported splicing mutations of STAR cause a severe impairment of protein function and phenotype.

Tissue coverage and neointimal hyperplasia in overlap versus nonoverlap segments of drug-eluting stents 9 to 13 months after implantation: in vivo assessment with optical coherence tomography

BACKGROUND Histologic experimental studies have reported incomplete neointimal healing in overlapping with respect to nonoverlapping segments in drug-eluting stents (DESs), but these observations have not been confirmed in human coronary arteries hitherto. On the contrary, angiographic and optical coherence tomography studies suggest that DES overlap elicits rather an exaggerated than an incomplete neointimal reaction. METHODS Optical coherence tomography studies from 2 randomized trials including sirolimus-eluting, biolimus-eluting, everolimus-eluting, and zotarolimus-eluting stents were analyzed at 9- to 13-month follow-up. Coverage in overlapping segments was compared versus the corresponding nonoverlapping segments of the same stents, using statistical pooled analysis. RESULTS Forty-two overlaps were found in 31 patients: 11 in sirolimus-eluting stents, 3 in biolimus-eluting stents, 17 in everolimus-eluting stents, and 11 in zotarolimus-eluting stents. The risk ratio of incomplete coverage was 2.35 (95% CI 1.86-2.98) in overlapping versus nonoverlapping segments. Thickness of coverage in overlaps was only 85% (95% CI 81%-90%) of the thickness in nonoverlaps. Significant heterogeneity of the effect was observed, especially pronounced in the comparison of thickness of coverage (I(2) = 90.31). CONCLUSIONS The effect of overlapping DES on neointimal inhibition is markedly heterogeneous: on average, DES overlap is associated with more incomplete and thinner coverage, but in some cases, the overlap elicits an exaggerated neointimal reaction, thicker than in the corresponding nonoverlapping segments. These results might help to understand why overlapping DES is associated with worse clinical outcomes, both in terms of thrombotic phenomena and in terms of restenosis and revascularization.

Unusual presentation of alveolar echinococcosis as prostatic and paraprostatic cysts in a dog

BACKGROUND: Alveolar echinococcosis (AE) is caused by the larval stage (metacestode) of Echinococcus multilocularis. The domestic dog can act as a definitive host and harbor adult cestodes in its small intestine or become an aberrant intermediate host carrying larval stages that may cause severe lesions in the liver, lungs and other organs with clinical signs similar to AE in humans. CASE PRESENTATION: A case of canine AE, affecting the liver and prostate with development of multilocular hydatid paraprostatic cysts and possible lung involvement is described in an 8-year-old neutered male Labrador retriever dog.The dog presented with progressive weight loss, acute constipation, stranguria and a suspected soft tissue mass in the sublumbar region. Further evaluation included computed tomography of the thorax and abdomen, which revealed cystic changes in the prostate, a paraprostatic cyst, as well as lesions in the liver and lungs. Cytological examination of fine-needle aspirates of the liver, prostate and paraprostatic cyst revealed parasitic hyaline membranes typical of an Echinococcus infection and the presence of E. multilocularis-DNA was confirmed by PCR. The dog was treated with albendazole and debulking surgery was considered in case there was a good response to antiparasitic treatment. Constipation and stranguria resolved completely. Six months after the definitive diagnosis, the dog was euthanized due to treatment-resistant ascites and acute anorexia and lethargy. CONCLUSIONS: To the authors' knowledge, this is the first publication of an E. multilocularis infection in a dog causing prostatic and paraprostatic cysts. Although rare, E. multilocularis infection should be considered as an extended differential diagnosis in dogs presenting with prostatic and paraprostatic disease, especially in areas where E. multilocularis is endemic.

A novel mutation L260P of the steroidogenic acute regulatory protein gene in three unrelated patients of Swiss ancestry with congenital lipoid adrenal hyperplasia.

CONTEXT Lipoid congenital adrenal hyperplasia (CAH) is the most severe form of CAH leading to impaired production of all adrenal and gonadal steroids. Mutations in the gene encoding steroidogenic acute regulatory protein (StAR) cause lipoid CAH. OBJECTIVE We investigated three unrelated patients of Swiss ancestry who all carried novel mutations in the StAR gene. All three subjects were phenotypic females with absent Müllerian derivatives, 46,XY karyotype, and presented with adrenal failure. METHODS AND RESULTS StAR gene analysis showed that one patient was homozygous and the other two were heterozygous for the novel missense mutation L260P. Of the heterozygote patients, one carried the novel missense mutation L157P and one had a novel frameshift mutation (629-630delCT) on the second allele. The functional ability of all three StAR mutations to promote pregnenolone production was severely attenuated in COS-1 cells transfected with the cholesterol side-chain cleavage system and mutant vs. wild-type StAR expression vectors. CONCLUSIONS These cases highlight the importance of StAR-dependent steroidogenesis during fetal development and early infancy; expand the geographic distribution of this condition; and finally establish a new, prevalent StAR mutation (L260P) for the Swiss population.

Early over-expression of GRP receptors in prostatic carcinogenesis

BACKGROUND The GRP receptor shows high over-expression in prostatic adenocarcinoma and high grade PIN, but low expression in normal prostate glands. This represents the molecular basis for GRP receptor imaging of prostate cancer with radioactive compounds. However, a focal, high density GRP receptor expression can be observed in hitherto uncharacterized prostate glands. METHODS GRP receptors were quantitatively measured with in vitro receptor autoradiography using ¹²⁵I-Tyr⁴ -bombesin in samples from 115 prostates. On successive tissue sections, ¹²⁵I-Tyr⁴ -bombesin autoradiography was compared with H&E staining and MIB-1 and 34βE12 immunohistochemistry. RESULTS On one hand, it was confirmed that GRP receptors were expressed in adenocarcinoma and high grade PIN in high density and high incidence (77% and 73%, respectively), but in normal prostate glands in low density and low frequency (18%). On the other hand, a novel and intriguing observation was the existence of focal non-invasive prostate glands with high GRP receptor density, characterized by low grade nuclear atypia and increased proliferation, compatible with lower grade PIN. There was a significant GRP receptor density gradient (P ≤ 0.005), increasing from normal prostate glands (mean relative optical density, ROD, of ¹²⁵I-Tyr⁴ -bombesin binding: 0.17) over atypical glands without increased MIB-1 labeling (0.28) and atypical glands with increased MIB-1 expression (0.44) to high grade PIN and adenocarcinoma (0.64 and 0.58, respectively). CONCLUSIONS GRP receptor over-expression may be a novel, specific marker of early prostatic neoplastic transformation, arising in low grade PIN, and progressively increasing during malignant progression. This should be considered when interpreting in vivo GRP receptor imaging in males.

Glucagon-like peptide-1 receptor imaging for the localisation of insulinomas: a prospective multicentre imaging study

BACKGROUND Small benign insulinomas are hard to localise, leading to difficulties in planning of surgical interventions. We aimed to prospectively assess the insulinoma detection rate of single-photon emission CT in combination with CT (SPECT/CT) with a glucagon-like peptide-1 receptor avid radiotracer, and compare detection rates with conventional CT/MRI techniques. METHODS In our prospective imaging study, we enrolled adults aged 25-81 years at centres in Germany, Switzerland, and the UK. Eligible patients had proven clinical and biochemical endogenous hyperinsulinaemic hypoglycaemia and no evidence for metastatic disease on conventional imaging. CT/MRI imaging was done at referring centres according to standard protocols. At three tertiary nuclear medicine centres, we used whole body planar images and SPECT/CT of the abdomen up to 168 h after injection of (111)In-[Lys40(Ahx-DTPA-(111)In)NH2]-exendin-4 ((111)In-DTPA-exendin-4) to identify insulinomas. Consenting patients underwent surgery and imaging findings were confirmed histologically. FINDINGS Between Oct 1, 2008, and Dec 31, 2011, we recruited 30 patients. All patients underwent (111)In-DTPA-exendin-4 imaging, 25 patients underwent surgery (with histological analysis), and 27 patients were assessed with CT/MRI. (111)In-DTPA-exendin-4 SPECT/CT correctly detected 19 insulinomas and four additional positive lesions (two islet-cell hyperplasia and two uncharacterised lesions) resulting in a positive predictive value of 83% (95% CI 62-94). One true negative (islet-cell hyperplasia) and one false negative (malignant insulinoma) result was identified in separate patients by (111)In-DTPA-exendin-4 SPECT/CT. Seven patients (23%) were referred to surgery on the basis of (111)In-DTPA-exendin-4 imaging alone. For 23 assessable patients, (111)In-DTPA-exendin-4 SPECT/CT had a higher sensitivity (95% [95% CI 74-100]) than did CT/MRI (47% [27-68]; p=0·011). INTERPRETATION (111)In-DTPA-exendin-4 SPECT/CT could provide a good second-line imaging strategy for patients with negative results on initial imaging with CT/MRI. FUNDING Oncosuisse, the Swiss National Science Foundation, and UK Department of Health.

Smooth Muscle Hyperplasia due to ACTA2/MYH11 Mutations: Identification of Novel Pathology and Pathways Leading to Aneurysms and Diverse Vascular Occlusive Diseases

Missense mutations in smooth muscle cell (SMC) specific ACTA2 (á-actin) and MYH11 (â-myosin heavy chain) cause diffuse and diverse vascular diseases, including thoracic aortic aneurysms and dissections (TAAD) and early onset coronary artery disease and stroke. The mechanism by which these mutations lead to dilatation of some arteries but occlusion of others is unknown. We hypothesized that the mutations act through two distinct mechanisms to cause varied vascular diseases: a loss of function, leading to decreased SMC contraction and aneurysms, and a gain of function, leading to increased SMC proliferation and occlusive disease. To test this hypothesis, ACTA2 mutant SMCs and myofibroblasts were assessed and found to not form á-actin filaments whereas control cells did, suggesting a dominant negative effect of ACTA2 mutations on filament formation. A loss of á-actin filaments would be predicted to cause decreased SMC contractility. Histological examination of vascular tissues from patients revealed SMC hyperplasia leading to arterial stenosis and occlusion, supporting a gain of function associated with the mutant gene. Furthermore, ACTA2 mutant SMCs and myofibroblasts proliferated more rapidly in static culture than control cells (p<0.05). We also determined that Acta2-/- mice have ascending aortic aneurysms. Histological examination revealed aortic medial SMC hyperplasia, but minimal features of medial degeneration. Acta2-/- SMCs proliferated more rapidly in culture than wildtype (p<0.05), and microarray analysis of Acta2-/- SMCs revealed increased expression of Actg2, 15 collagen genes, and multiple focal adhesion genes. Acta2-/- SMCs showed altered localization of vinculin and zyxin and increased phosphorylated focal adhesion kinase (FAK) in focal adhesions. A specific FAK inhibitor decreased Acta2-/- SMC proliferation to levels equal to wildtype SMCs (p<0.05), suggesting that FAK activation leads to the increased proliferation. We have described a unique pathology associated with ACTA2 and MYH11 mutations, as well as an aneurysm phenotype in Acta2-/- mice. Additionally, we identified a novel pathogenic pathway for vascular occlusive disease due to loss of SMC contractile filaments, alterations in focal adhesions, and activation of FAK signaling in SMCs with ACTA2 mutations.

Quantitative analysis of benign paroxysmal positional vertigo fatigue under canalithiasis conditions

In our daily life, small flows in the semicircular canals (SCCs) of the inner ear displace a sensory structure called the cupula which mediates the transduction of head angular velocities to afferent signals. We consider a dysfunction of the SCCs known as canalithiasis. Under this condition, small debris particles disturb the flow in the SCCs and can cause benign paroxysmal positional vertigo (BPPV), arguably the most common form of vertigo in humans. The diagnosis of BPPV is mainly based on the analysis of typical eye movements (positional nystagmus) following provocative head maneuvers that are known to lead to vertigo in BPPV patients. These eye movements are triggered by the vestibulo-ocular reflex, and their velocity provides an indirect measurement of the cupula displacement. An attenuation of the vertigo and the nystagmus is often observed when the provocative maneuver is repeated. This attenuation is known as BPPV fatigue. It was not quantitatively described so far, and the mechanisms causing it remain unknown. We quantify fatigue by eye velocity measurements and propose a fluid dynamic interpretation of our results based on a computational model for the fluid–particle dynamics of a SCC with canalithiasis. Our model suggests that the particles may not go back to their initial position after a first head maneuver such that a second head maneuver leads to different particle trajectories causing smaller cupula displacements.