Diagnosis and management of congenital hypopituitarism in children

Hypopituitarism (or pituitary deficiency) is a rare disease with an estimated prevalence of between 1/16,000 and 1/26,000 individuals, defined by insufficient production of one or several anterior pituitary hormones (growth hormone [GH], thyroid-stimulating hormone [TSH], adrenocorticotropic hormone [ACTH], luteinizing hormone [LH], follicle-stimulating hormone [FSH], prolactin), in association or not with diabetes insipidus (antidiuretic hormone [ADH] deficiency). While in adults hypopituitarism is mostly an acquired disease (tumors, irradiation), in children it is most often a congenital condition, due to abnormal pituitary development. Clinical symptoms vary considerably from isolated to combined deficiencies and between syndromic and non-syndromic forms. Early signs are non-specific but should not be overlooked. Diagnosis is based on a combination of clinical, laboratory (testing of all hormonal axes), imaging (brain magnetic resonance imaging [MRI] with thin slices centered on the hypothalamic-pituitary region), and genetic (next-generation sequencing of genes involved in pituitary development, array-based comparative genomic hybridization, and/or genomic analysis) findings. Early brain MRI is crucial in neonates or in cases of severe hormone deficiency for differential diagnosis and to inform syndrome workup. This article presents recommendations for hormone replacement therapy for each of the respective deficient axes. Lifelong follow-up with an endocrinologist is required, including in adulthood, with multidisciplinary management for patients with syndromic forms or comorbidities. Treatment objectives include alleviating symptoms, preventing comorbidities and acute complications, and optimal social and educational integration.

Male genital lichen planus: A retrospective study of 89 cases

BACKGROUND

Unlike other types of lichen planus (LP), there are no series concerning male genital LP.

OBJECTIVE

To describe the clinical characteristics, diagnosis, and response to treatment of male genital LP.

PATIENTS AND METHODS

A retrospective study of male patients with genital LP consulting a dermatologist specialized in anogenital diseases between January 2010 and 2019. Demographic data, history, functional signs, clinical characteristics, pathology, complications, and treatment efficacy were collected.

RESULTS

Eighty-nine patients were included at four centers. The median age was 51 years. Most patients were uncircumcised and asymptomatic. In 88.8% of cases, only the genital mucosa was involved. Erythema (71%), papules (21.3%), lacy network (15.7%), atrophic lesions (15.7%), erosions (14.6%), and post-inflammatory hyperpigmentation (2.2%) were less frequently observed. Biopsy results confirmed LP in 61.3% of cases but could not rule out other inflammatory genital dermatoses in other cases. Anatomic complications were observed in 30.3% of patients. Topical corticosteroids (TCS) induced remission in most cases. Tacrolimus efficacy was comparable to that of TCS.

CONCLUSION

Male genital LP is a rare inflammatory disorder chiefly affecting uncircumcised men. It is found predominantly on the mucosal component of the penis and presents as non-erosive inflammatory balanitis in most cases, with frequent partial or complete remission on treatment with TCS.

[Penile malakoplakia associated with lichen sclerosus]

INTRODUCTION

Malakoplakia is a granulomatosis of infectious origin in reaction to a chronic bacterial infection (most commonly urinary Escherichiacoli) related to an acquired phagocytosis impairment.

PATIENTS AND METHODS

We report a case of penile malakoplakia in a 69-year-old man with lichen sclerosis and stenosis of the urinary meatus leading to recurrent urinary tract infections. The clinical aspect was suggestive of squamous cell carcinoma of the glans developing on lichen sclerosus, but histological examination revealed penile malakoplakia.

DISCUSSION

Malakoplakia of the genital mucosa is rare, with only one case of involvement of the glans being reported in the literature. The association with lichen sclerosus is probably not fortuitous but could in fact be due to chronic urinary tract infection favored by stenosis of the urethral meatus and possible local immunodepression following prolonged application of clobetasol.

CONCLUSION

We report a case of penile malakoplakia associated with chronic E. coli urinary tract infection, due originally to associated genital lichen sclerosus.

[Community-acquired acute maxillary sinusitis or rhinosinusitis in adults in France: current management]

Sinus infections, often viral, are a common reason for physician visits. The multiplicity of clinical presentations makes its diagnosis difficult. The problem is to recognize bacterial infection without additional testing, except in cases of treatment failures, complications or relapse. Patients with signs suggestive of rhinosinusitis fall into one of four basic clinical situations: common colds, 'doubtful' rhinosinusitis, apparent acute maxillary bacterial rhinosinusitis, and complications. Anterior rhinoscopy may help confirm diagnosis. Current bacterial epidemiology is based on the results of clinical studies, microbial ecology, and samples taken in cases of treatment failure. The two bacteria isolated most frequently are Streptococcus pneumoniae and Haemophilus influenzae, both of which pose resistance problems. Moraxella catarrhalis, Streptococcus pyogenes and Staphylococcus aureus are isolated less often. The dominant issue in management of acute rhinosinusitis is whether to use antibiotic or symptomatic treatment. For viral infections, antibiotic therapy is useless and highly inadvisable. For 'doubtful' infections, symptomatic treatment is likely to lead to recovery. The use of non-recommended antibiotics also increases the risk of selection of resistant bacteria. When bacterial rhinosinusitis is strongly suspected, recourse to antibiotic treatment is recommended in view of the benefits in this situation (AFSSAPS 2005). This treatment is probabilistic, should be decided at the end of the consultation, and follows the AFSSAPS guidelines.

Effects of aging on the cardiac remodeling induced by chronic high-altitude hypoxia in rat

Effects of chronic high-altitude hypoxia on the remodeling of right ventricle were examined in three age groups of rats: 2, 6, and 18 mo. The extent of right ventricular (RV) hypertrophy (RVH) showed an age-associated diminution. RV cell size and pericellular fibrosis showed a significant increase in the 2- and 6-mo-old exposed rats but not in the 18-mo-old exposed rats compared with control. A hyperplasic response was underscored in the three exposed age groups but appeared less pronounced in the 18-mo-old rats. A significant decrease in the transient outward potassium current (Ito) density was observed in RV cell only in the 2-mo-old exposed group compared with the control group. In the control group, there was a clear tendency for Ito density to decrease as a function of age. The sustained outward current density was modified neither by the hypoxia condition nor by the age. Neither the cytochrome c oxidase activity nor the heat shock protein 72 content in the RV was altered after hypoxic exposure regardless of age. The norepinephrine content in the RV was significantly decreased in each age group exposed to hypoxia when compared with their age-matched control group. Our findings indicate that the remodeling (at morphological and electrophysiological levels) induced by chronic hypoxia in the RV can be decreased by the natural aging process.

Reversibility of electrophysiological changes induced by chronic high-altitude hypoxia in adult rat heart

Recent studies indicate that regression of left ventricular hypertrophy normalizes membrane ionic current abnormalities. This work was designed to determine whether regression of right ventricular hypertrophy induced by permanent high-altitude exposure (4,500 m, 20 days) in adult rats also normalizes changes of ventricular myocyte electrophysiology. According to the current data, prolonged action potential, decreased transient outward current density, and increased inward sodium/calcium exchange current density normalized 20 days after the end of altitude exposure, whereas right ventricular hypertrophy evidenced by both the right ventricular weight-to-heart weight ratio and the right ventricular free wall thickness measurement normalized 40 days after the end of altitude exposure. This morphological normalization occurred at both the level of muscular tissue, as shown by the decrease toward control values of some myocyte parameters (perimeter, capacitance, and width), and the level of the interstitial collagenous connective tissue. In the chronic high-altitude hypoxia model, the regression of right ventricular hypertrophy would not be a prerequisite for normalization of ventricular electrophysiological abnormalities.

Voltage-gated sodium channel (SkM1) content in dystrophin-deficient muscle

The membrane cytoskeleton is increasingly considered as both an anchor and a functional modulator for ion channels. The cytoskeletal disruptions that occur in the absence of dystrophin led us to investigate the voltage-gated sodium channel (SkM1) content in the extensor digitorum longus (EDL) muscle of the dystrophin-deficient mdx mouse. Levels of SkM1 mRNA were determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). A C-terminal portion of the mouse-specific SkM1 alpha-subunit cDNA (mScn4a) was identified first. SkM1 mRNA levels were as abundant in mdx as in normal muscle, thus suggesting that the transcriptional rate of SkM1 remains unchanged in mdx muscle. However, SkMI density in the extrajunctional sarcolemma was shown to be significantly reduced in mdx muscle, using confocal immunofluorescence image analysis. This decrease was found to be associated with a reduction in the number of SkM1-rich fast-twitch IIb fibres in mdx muscle. In addition, lowered SkM1 sarcolemmal labelling was found in all mdx fibres regardless of their metabolic type. These results suggest the existence of a perturbation of SkM1 anchorage to the plasma membrane. Such an alteration is likely to be related to the 50% decrease in mdx muscle of the dystrophin-associated syntrophins, which are presumed to be involved in SkM1 anchorage. However, the moderate reduction in SkM1 density (-12.7%) observed in mdx muscle argues in favour of a non-exclusive role of syntrophins in SkM1 anchorage and suggests that other membrane-associated proteins are probably also involved.

Visualization of the subsarcolemmal cytoskeleton network of mouse skeletal muscle cells by en face views and application to immunoelectron localization of dystrophin

The ultrastructural organization of the highly interconnected filamentous network underneath the sarcolemma as well as the role played by the muscle protein dystrophin within this cytoskeleton remain yet unclear. More accurate information has been obtained by using a method which provides three-dimensional en face views of large membrane areas applied to mouse cultured myotubes and isolated adult skeletal muscle fibres. Two levels have been distinguished in the cytoskeleton underlying the sarcolemma: the submembranous level, partly integrated into the membrane, and the cortical level, invading the proximal cytoplasmic space. Few differences have been found between the membrane cytoskeletons of myotubes issued from 14-day-old cultures and those of adult fibres. The comparison was done with cells where dystrophin is missing (mdx mouse muscle): surprisingly, the lack of dystrophin does not induce obvious or dramatic ultrastructural disorganization, either in the cortical cytoskeletal network or in the submembranous one. Immunogold labelling of either the central-rod or the C-terminal domain of dystrophin is not located among the cortical network. This study provides additional data on the spatial ordering of subsarcolemmal cytoskeletal elements: dystrophin does not appear as a filamentous structure entirely located among subsarcolemmal cytoskeleton but seems partly embedded in membranous material.

Inward barium current and excitation-contraction coupling in frog twitch muscle fibres

The role of barium ions in excitation-contraction coupling was studied in single isolated frog semitendinosus fibres. Simultaneous recordings of membrane currents and contraction under voltage-clamp conditions in a sucrose-vaseline gap device show that barium ions have a reversible inhibiting effect on contraction. This inhibiting action was correlated to the entry of barium ions via the DHP-sensitive tubular calcium channel. Cytological observations and X-ray microanalysis performed on the fibres used in the electrophysiological experiments indicate that barium ions do not accumulate in the junctional sarcoplasmic reticulum; they can freely diffuse in the intermyofibrillar space and they accumulate in mitochondria. Calcium release experiments performed on isolated sarcoplasmic reticulum vesicles show that barium ions are not able to induce calcium release from calcium-loaded vesicles, they behave as calcium release inhibitors. These results are discussed in relation with the possible role of the slow Ca current in excitation-contraction coupling.

X-ray microanalysis of calcium containing organelles in resin embedded tissue

The localization of calcium in cell organelles at the electron microscope level is often achieved through cytochemical techniques, and verified by X-ray microanalysis. Various methods have been used to cytochemically detect calcium or calcium-binding sites: calcium loading, calcium substitution by strontium, barium, or even lead, and calcium precipitation by oxalate, phosphate, fluoride, or pyroantimonate. Their results may have heuristic value, particularly in preliminary studies of poorly known cell types. A complementary and more physiological approach is offered by quantitative measurement of the total calcium content of organelles after cryofixation. Resin embedding is less demanding than cryomicrotomy and gives better images: it can be used after cryosubstitution in the presence of oxalic acid. This technique was tested, and applied to several cell types.

Increase in the calcium content of cardiac tissue after postfixation with osmium tetroxide

The concentration of osmium has been measured by destructive chemical analysis in glutaraldehyde fixed heart tissue postfixed with osmium tetroxide and embedded in epoxy resin. After such treatment, the mean atomic number of the specimen (Z) is close to 10, which permits a quantitative analysis of calcium (Ca) by the continuum method, using Z2/A as a correcting factor (A: atomic weight). Wavelength-dispersive X-ray microanalysis has been used to determine the Ca concentration of frog cardiac tissue fixed in glutaraldehyde and embedded in resin. These measurements have been repeated on tissue postfixed in osmium tetroxide; contrary to expectations, the apparent Ca concentration is much higher in osmium treated than in nontreated tissue. However, this result is observed with OsO4 solutions prepared in glass, not with solutions prepared in plastic. It is shown by energy dispersive X-ray analysis of droplets that OsO4 solutions prepared in glass contain large amounts of calcium, potassium and silicon. Care must be taken in preparing OsO4 fixatives when the fixed tissues are to be subjected to X-ray microanalysis of such elements as Ca or Si.

Quantitative X-ray microanalysis of calcium with the Camebax-TEM system in frozen, freeze-substituted and resin-embedded tissue sections. Application to molluscan glio-interstitial granules

The relevance of the continuum method for a quantitative X-ray microanalysis of epon embedded tissue sections in the particular conditions offered by the Camebax-TEM system was tested and an improved model of specimen holder is proposed. The absolute calcium concentration [Ca] of membrane-bound intracellular glio-interstitial granules was determined by X-ray microanalysis in transmission electron microscopy of Mytilus retractor muscle. The Ca peak and background values were measured by the wavelength-dispersive spectrometer of the Camebax; the mass thickness of the section was recorded simultaneously with an added energy-dispersive detector. The tissue was frozen at approximately equal to 77 K in a mixture of liquid propane and butane, freeze-substituted in the presence of oxalic acid and embedded in epoxy resin. The calcium concentration of glio-interstitial granules can be as high as 180 mmol.kg-1 of epoxy-embedded tissue, with an average of 40 mmol.kg-1. The sampling of the data through repeated experiments is discussed and it is proposed that the cell would be the main level of variation. The Ca content of glio-interstitial granules is significantly lower in the tissues of animals submitted to high-potassium artificial sea-water for 10 min. This finding was predicted by the hypothesis that glio-interstitial tissue is a regulator of calcium concentration in extracellular spaces.

Correlations between ultrastructural features and contraction rates in rotiferan muscle. I. Preliminary observations on longitudinal retractor muscles in Trichocerca rattus

The Rotifer Trichocerca rattus has striated longitudinal retractor muscles. These muscles can be divided into two categories: 1. The central and ventral retractor muscles which, after fixation, are found in a supercontracted state: they probably contract very quickly. 2. The lateral retractor muscles which are in a relaxed state after fixation. However, if the animal is mechanically stimulated before fixation, these are also fixed in a contracted state: so, normally, these muscles probably contract more slowly than the first category. In the relaxed state, thin myofilaments of the lateral retractor muscles are folded at the I band level; this a consequence of their compression provoked by the contraction of central and ventral retractor muscles. In muscles of the first type, the thick myofilaments are shorter (less than 2 mu) than in the second type (2.5 mu).

Distribution of the glio-interstitial system in molluscs. II. Electron microscopy of tonic and phasic muscles in the digestive tract of Aplysia and other opisthobranchs

The muscular walls of the buccal mass and the oesophagus of Aplysia rosea and Glossodoris tricolor were studied by electron microscopy. The cytological features of the muscle cells, neuro-muscular junctions and a neuro-glial junction are described. This junction between an axon and a teloglial process, in the oesophagus of Aplysia, possesses all the cytological differentiations of a typical molluscan synapse. Particular attention is drawn to the distribution of the glio-interstitial tissue and the size of the extracellular spaces in these muscular organs. The classification of these muscle into 'tonic' and 'phasic' types is discussed. From this study and other data, it is concluded that the development of the glio-interstitial tissue in the muscular organs of molluscs is correlated with the size of the extracellular spaces rather than with the type of contraction of the muscle.