Nueva mutación identificada en el gen FOXP3 en lactante menor con diarrea crónica como manifestación de enteropatía autoinmune - síndrome IPEX / New mutation in FOXP3 gene identified in an infant with chronic diarrhea as manifestation of autoinmune enteropathy - IPEX syndrome

INTRODUCCIÓN: El síndrome IPEX (inmunodesregulación, poliendocrinopatía y enteropatía autoinmune ligada a X) causado por mutaciones en el gen FOXP3, se caracteriza por diarrea prolongada, alteraciones endocrinológicas y dermatitis. El tratamiento consiste en la administración de medicamentos inmunosupresores, siendo el trasplante de médula ósea la única cura potencial. OBJETIVO: Describir una nueva mutación del gen FOXP3, así como los hallazgos y evolución de un paciente con síndrome IPEX. CASO CLÍNICO: Lactante menor masculino que debutó al mes de vida con diarrea cró nica, falla intestinal e infecciones recurrentes. Exámenes de laboratorio y biopsia intestinal sugerentes de enteropatía autoinmune. Durante el seguimiento, el paciente presentó refractariedad al manejo inmunosupresor con esteroides, ciclosporina y tacrolimus, falleciendo a los 7 meses de edad por complicaciones vasculares. Antecedente familiar por línea materna de múltiples muertes en hombres menores de 1 año. Ante la sospecha de síndrome IPEX se realizó exoma en trío que reportó una mutación probablemente patogénica en el gen FOXP3. CONCLUSIÓN: Se documentó una nueva mutación del gen FOXP3 en paciente con síndrome IPEX. A pesar de la baja prevalencia de esta enfermedad, es importante el reconocimiento de síntomas no específicos pero sugerentes del diagnóstico.

INTRODUCTION: The IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked) syn drome is caused by the mutations of the FOXP3 gene, characterized by persistent diarrhea, endo crine disorders, and dermatitis. The treatment is the administration of immunosuppressive drugs, where hematopoietic stem cell transplantation is the only potential cure. OBJECTIVE: To describe a new FOXP3 gene mutation, as well as the findings and evolution of a patient with IPEX syndrome. CLINICAL CASE: Male infant presenting at one month of age with chronic diarrhea, intestinal failure, and recurrent infections. Lab tests and intestinal biopsy suggested autoimmune enteropathy. During follow-up, the patient presented resistance to immunosuppressive treatment with corticosteroids, cyclosporine, and tacrolimus, dying at 7 months of age due to vascular complications. He had a ma ternal family history of multiple deaths of men under 1 year of age. IPEX syndrome was suspected therefore a trio whole-exome sequencing was performed that showed a probably pathogenic FOXP3 gene mutation. CONCLUSION: A new FOXP3 gene mutation is reported in a patient with IPEX syndro me. Despite the low prevalence of this disease, it is important to recognize non-specific but suggestive symptoms for its diagnosis.

Diagnóstico genético de pacientes con agammaglobulinemia primaria atendidos en centros peruanos de tercer nivel / Genetic diagnosis of patients with primary agammaglobulinemia treated at third level peruvian centers

Las agammaglobulinemias primarias (AP) resultan de alteraciones específicas en las células B, lo cual, conduce a baja producción de anticuerpos. La sospecha diagnóstica se establece con el antecedente de infecciones a repetición, inmunoglobulinas bajas y la ausencia linfocitos B CD19+. El diagnóstico se confirma mediante el análisis genético y la detección de una mutación ligada en el cromosoma X o autosómico recesiva o dominante. En Perú, no hay literatura sobre AP ni reportes sobre el genotipo de los pacientes con sospecha de AP. Bajo este escenario, se realizó un estudio que describió el genotipo de pacientes con sospecha de AP. Se encontraron 20 pacientes con mutaciones en el gen BTK y una mutación autosómica recesiva IGHM. Se hallaron 13 mutaciones hereditarias y siete mutaciones de novo. Se concluye que las AP son, en su mayoría, mutaciones en el gen BTK que corresponden con AP ligadas al cromosoma X.

Primary agammaglobulinemia result from specific alterations in B cells, which lead to low antibody production. Diagnostic suspicion is established with a history of repeated infections, low immunoglobulins, and absence of CD19+ B lymphocytes. The diagnosis is confirmed by genetic analysis and the detection of a mutation linked to the X or autosomal recessive or dominant chromosome. In Peru, there is no literature on primary agammaglobulinemia and no reports on the genotype of patients with suspected primary agammaglobulinemia. Under this scenario, a study was performed to describe the genotype of patients with suspected primary agammaglobulinemia. Twenty (20) patients were found with mutations in the BTK gene and an autosomal recessive IGHM mutation. Thirteen (13) hereditary mutations and seven de novo mutations were found. It is concluded that the group of primary agammaglobulinemia are mostly mutations in the BTK gene, corresponding to X-linked agammaglobulinemia.

Propiedades psicométricas de la escala EMUN-AR determinadas mediante el análisis de Rasch / Psychometric variables of the EMUN-AR scale using Rasch analysis

Resumen Introducción. Las escalas de autorreporte se han considerado útiles para evaluar y vigilar los síntomas de la enfermedad maníaco-depresiva. Uno de estos instrumentos, la escala de medición de la enfermedad maníaco-depresiva mediante autorreporte (EMUN-AR), no se ha validado aún. Objetivo. Validar la escala EMUN-AR usando el modelo de Rasch. Materiales y métodos. La escala EMUN-AR mide 26 ítems que evalúan por dimensiones los síntomas de la enfermedad maníaco-depresiva en tres categorías: frecuencia, intensidad y grado de molestia causada. Para evaluar las propiedades psicométricas de la escala, se efectuaron análisis factoriales exploratorios con el fin de tener una aproximación de su estructura latente, y se usaron modelos de Rasch que incluyeron la 'unidimensionalidad', la confiabilidad, el ajuste de ítems, el ordenamiento de umbrales, y los mapas de personas e ítems. Resultados. Se seleccionó una muestra de 267 pacientes hospitalizados, 204 de los cuales había sufrido un episodio maníaco (76,4 %) y estaba recibiendo tratamiento farmacológico. Se encontró una estructura factorial que puede resumirse en cuatro dominios: activación, inhibición, ideas depresivas e inadaptación. El análisis de Rasch evidenció la unidimensionalidad en los factores, adecuados valores de confiabilidad, buen ajuste de los 26 ítems en general (excepto en el ítem que mide las ideas de muerte o suicidio), un funcionamiento deficiente del sistema de calificación de los ítems y un cubrimiento limitado de los síntomas de la enfermedad correspondientes a las formas atenuadas. Conclusión. Se modificó la escala original en dos aspectos: se ajustó un ítem cuyos indicadores marginales tenían mal ajuste y se redujo el número de categorías. En su forma actual, el instrumento es apropiado para medir las formas graves de la enfermedad maníaco-depresiva, mas no así las atenuadas.

Abstract Introduction: Self-report scales have been considered to be useful for evaluating and monitoring symptoms of manic-depressive illnesses. The EMUN-AR scale is one of such scales but it has not been validated. Objective: To validate the EMUN-AR scale using Rasch models. Materials and methods: The EMUN-AR scale measures 26 items to assess comprehensively symptoms of manic-depressive illnesses in three domains: Frequency, severity, and level of disturbance caused by the symptoms. To test the psychometric properties of this scale, we used the exploratory factorial and Rasch analyses. The Rasch analysis included unidimensionality, reliability, item fit, threshold ordering, and person-item maps. Results: The study included 267 hospitalized patients, most of them with a manic episode diagnosis (n=204, 76.4%), and receiving pharmacological treatment. The factor structure was summarized in four domains: Activation, inhibition, depressive ideation, and maladaptive behavior. The Rasch analysis supported unidimensionality of the EMUN-AR factors, satisfactory levels of reliability, and appropriate item fit, except for one of the items measuring death or suicidal thoughts. However, the scale did not measure adequately the mild forms of the illness given its redundant and unordered thresholds. Conclusion: The EMUN-AR was modified in two aspects: An item whose marginal indicators were poorly adjusted and the reduction in the number of categories. In its current form, the EMUN-AR is appropriate for measuring severe forms of the illnesses, but it does not adequately measure the mild forms of manic-depressive illnesses.

Inmunodeficiencias primarias en niños gravemente enfermos: a propósito de 3 casos clínicos / Primary immunodeficiencies in seriously ill children: Report of 3 clinical cases

Las inmunodeficiencias primarias (IDP) son enfermedades congénitas causadas por alteraciones cuantitativas o funcionales de la respuesta inmunitaria. Se caracterizan por predisposición a infecciones, autoinmunidad, alergia y enfermedades linfoproliferativas. Objetivo: Reportar 3 casos de lactantes menores con IDP que se manifestaron como infecciones graves de curso inhabitual. Casos clínicos: Se presentan 3 pacientes diagnosticados como IDP en su estadía en la Unidad de Paciente Crítico Pediátrico. El primero corresponde a un lactante de 4 meses con neumonía multifocal extensa a quien se diagnosticó un síndrome de inmunodeficiencia combinada severa ligada a X; el segundo es un lactante de 8 meses que se manifestó como una adenitis mesentérica por Candida lusitaniae y que correspondió a enfermedad granulomatosa crónica, y el tercero se trata de un lactante de 6 meses que se presentó con un ectima por Pseudomona y se diagnosticó una agammaglobulinemia ligada a X. Conclusión: El diagnóstico de IDP debe sospecharse en presencia de una infección de evolución arrastrada que no responde a tratamiento habitual. Se discuten los casos y se presenta una puesta al día de las patologías diagnosticadas.

Primary immunodeficiency diseases (PID) are congenital disorders secondary to an impaired immune response. Infections, autoimmune disorders, atopy, and lymphoproliferative syndromes are commonly associated with this disorder. Objective: To present and discuss 3 infants diagnosed with PID. Clinical cases: The cases are presented of three patients with PID diagnosed during their first admission to a Paediatric Intensive Critical Care Unit. The first patient, a 4-month-old infant affected by a severe pneumonia, and was diagnosed as a Severe Combined Immunodeficiency Disease. The second patient was an 8-month-old infant with Candida lusitaniae mesenteric adenitis, and diagnosed with a Chronic Granulomatous Disease. The last patient, a 6-month-old infant presented with ecthyma gangrenosum and X-linked agammaglobulinaemia. Conclusion: PID should be suspected when an infectious disease does not responde to the appropriate therapy within the expected period. An update of each disease is presented.

Retinosquise juvenil ligada ao X / X-linked juvenile retinoschisis

Relatar o caso de um paciente masculino de 28 anos que foi encaminhado ao Centro de Estudos e Pesquisas Oculistas Associados (RJ) para avaliação de retina e apresentou os achados típicos de retinosquise juvenil ligada ao cromossomo X: maculopatia cistóide com formação de cistos na fóvea e retinosquise periférica. Foi realizado o manejo conservador, com atenção para as complicações.

Report the case of a male 28 years-old patient, who was referred to Centro de Estudos e Pesquisas Oculistas Associados – RJ, to retina assessment and presented the tipical findings of the X-Linked Juvenile Retinoschisis: A cystoid maculopathy with formation of foveal cysts and schisis of the peripheral retina. It was carried out the conservative management, with attention to the complications.

Use of dermoscopy in the diagnosis of temporal triangular alopecia

Temporal triangular alopecia, also referred as congenital triangular alopecia, is an uncommon dermatosis of unknown etiology. It is characterized by a non-scarring, circumscribed alopecia often located unilaterally in the frontotemporal region. It usually emerges at ages 2-9 years. Alopecia areata is the main differential diagnosis, especially in atypical cases. Dermoscopy is a noninvasive procedure that helps distinguish temporal triangular alopecia from aloepecia areata. Such procedure prevents invasive diagnostic methods as well as ineffective treatments.

Sobre el carácter indiciario del método clínico: una mirada antropológica a partir de un relato de caso publicado / On the indiciary nature of the clinical method: an anthropological view of a published case study

En este artículo presentamos un relato de caso publicado como objeto de reflexión, sobre el que se realizó una reconstrucción parcial del proceso de estudio y una elaboración diagnóstica del síndrome Uruguay, mostrando las circunstancias del caso, la selección e interpretaciones de "pistas", y algunos de los detalles que fueron relevantes en el raciocinio clínico. Nuestro punto de partida es el reconocimiento del carácter narrativo del conocimiento clínico y del método clínico como un método indiciario. El manuscrito del síndrome Uruguay presenta una estructura narrativa ajustada a las convenciones del artículo científico que pone al método clínico en un segundo plano. Nuestros encuentros metódicos fueron diversos y comprendieron, sobre todo, entrevistas en profundidad a los autores del manuscrito y observaciones en su lugar de trabajo. El texto propone recuperar las historias de trabajo basadas en un modelo de conocimiento indiciario o semiótico y reconocer su importancia en la práctica médica.

In this article we present a published case study as an object of reflection. On this basis, we carried out a partial reconstruction of the process of study and diagnostic elaboration of the Uruguay syndrome, showing the circumstances of the case, the selection and interpretation of "clues," and some of the details relevant to the clinical reasoning. Our starting point is the recognition of the narrative nature of clinical knowledge and of the clinical method as an indiciary method. The manuscript of the Uruguay syndrome has a narrative structure adjusted to the conventions of a scientific article, which gives lesser importance to the clinical method. We carried out diverse methodical encounters, mainly involving in-depth interviews with the authors of the manuscript and observation in their workplace. The text seeks to recover the histories of work based on the indiciary or semiotic model of knowledge, and recognize the importance of this model in medical practice.

Case for diagnosis

A 6 year-old patient began to experience localized hairloss in the right temporal region three years ago. During the first appointment, diagnoses of alopecia areata and congenital triangular alopecia were made. After one year, there was no change. Upon dermatological examination, non-scarring alopecia was noted in the right temporal region, revealing extremely fine and fair hair follicles. A dermoscopy revealed only thin vellus-type hairs. Congenital triangular alopecia is a condition commonly confused with alopecia areata and is thus underdiagnosed. However, well-established clinical parameters and dermoscopic criteria can be used to distinguish skin diseases that affect hair and define the diagnosis.

Clinical features and management of hereditary spastic paraplegia / Aspectos clinicos e manejo das paraplegias espasticas hereditarias

Hereditary spastic paraplegia (HSP) is a group of genetically-determined disorders characterized by progressive spasticity and weakness of lower limbs. An apparently sporadic case of adult-onset spastic paraplegia is a frequent clinical problem and a significant proportion of cases are likely to be of genetic origin. HSP is clinically divided into pure and complicated forms. The later present with a wide range of additional neurological and systemic features. To date, there are up to 60 genetic subtypes described. All modes of monogenic inheritance have been described: autosomal dominant, autosomal recessive, X-linked and mitochondrial traits. Recent advances point to abnormal axonal transport as a key mechanism leading to the degeneration of the long motor neuron axons in the central nervous system in HSP. In this review we aim to address recent advances in the field, placing emphasis on key diagnostic features that will help practicing neurologists to identify and manage these conditions.

Paraplegias espásticas hereditárias (PEH) constituem um grupo de desordens geneticamente determinadas caracterizadas por espasticidade e paraparesia de progressão insidiosa. Paraplegia espástica aparentemente esporádica de início no adulto constitui problema frequente na prática neurológica. Evidências recentes sugerem que uma proporção significativa destes casos é geneticamente determinada. O grupo das PEH é dividido clinicamente em formas puras e complicadas de acordo com a concomitância de outras manifestações clinicas e neurológicas. Até o momento 60 tipos genéticos foram identificados. Todos os modos de herança monogênica já foram descritos: autossômica dominante, autossômica recessiva, ligada ao X e mitocondrial. Avanços recentes indicam que alterações do transporte axonal estão implicadas na degeneração dos longos axônios motores no sistema nervoso central na PEH. Nesta revisão abordamos recentes avanços na área com ênfase nos aspectos clínicos chave que ajudam o neurologista geral no diagnóstico e manejo correto deste grupo de doenças.

Anomalías inusuales del arco branquial, dermoepidérmicas y del sistema nervioso en un neonato con el síndrome VACTERL-H / Unusual branchial arch, dermoepidermal and nervous system anomalies in a neonate with VACTERL-H syndrome

El síndrome VACTERL-H es un trastorno complejo de malformaciones congénitas que implica vértebras, ano, corazón, tráquea, esófago, riñones, extremidades (del inglés limbs) e hidrocefalia. Su etiología se ha identificado sólo en algunos pacientes debido, en gran medida, a su naturaleza esporádica, así como a su alto grado de heterogeneidad clínica. En este informe se presenta a un neonato con el síndrome VACTERL-H, al que se asocian anomalías inusuales del arco branquial, dermoepidérmicas y del sistema nervioso, que se comparan con las descritas en la bibliografía médica. Según nuestra experiencia, esta presentación no sólo amplía el conocimiento del espectro de anomalías que se puede presentar en el síndrome VACTERL-H, sino que también podría ser útil en la identificación de pacientes con este fenotipo heterogéneo.

VACTERL-H syndrome is a complex disorder of congenital malformations that implies vertebrae, anus, heart, trachea, esophagus, kidneys, limbs and hydrocephalus. Its etiology has been identified in a fraction of patients largely due to their sporadic nature and its high degree of clinical heterogeneity. This report presents a newborn with VACTERL-H syndrome, associated with unusual branchial arch, dermoepidermal and nervous system anomalies, which are compared with those described in the medical literature. Based on our experience, the presentation of this case not only expands the knowledge of the spectrum of anomalies that can occur in VACTERL-H syndrome, but also can be useful in identifying patients with this heterogeneous phenotype.

A recurrent mutation in Moroccan patients with Dyggve-Melchior-Clausen syndrome: Report of a new case and review.

Dyggve-Melchior-Clausen (DMC) syndrome is a rare autosomal recessive disorder. It is a spondyloepimetaphyseal dysplasia associated with mental retardation. Clinical manifestations include coarse facies, microcephaly, short trunk dwarfism, and mental retardation. Mutations in Dymeclin gene (DYM), mapped to chromosome 18q21.1, is responsible for DMC. We report here the observation of a consanguineous Moroccan patient having DMC syndrome. The molecular studies showed a previously reported homozygous mutation at c.1878delA of DYM gene. We discuss this recurrent mutation in Moroccan patients with DMC syndrome with a review.

Incontinência pigmentar ligada ao X ou síndrome de Bloch-Sulzberger: relato de um caso / X-linked incontinentia pigmenti or Bloch-Sulzberger syndrome: a case report

A incontinência pigmentar é uma genodermatose rara, ligada ao X, que afeta, principalmente, neonatos do sexo feminino. As manifestações cutâneas são as mais prevalentes, e ocorrem em quatro fases bem distintas. Lactente feminina com lesões vesicobolhosas em tronco e membros e lesão verrucosa em palma. À biopsia, observou-se exocitose eosinofílica e derrame pigmentar, compatível com a suspeita clínica. Apesar de incomum, a incontinência pigmentar deve ser lembrada entre os diagnósticos diferenciais, de lesões vesicobolhosas e verrucosas da infância.

Incontinentia pigmenti is a rare X-linked genodermatosis that affects mainly female neonates. Skin manifestations are the most common and occur in four quite distinct phases. A female infant presented vesiculobullous lesions on trunk and limbs, and a verrucous lesion on the right palm. Biopsy revealed eosinophil exocytosis and pigment incontinence, confirming the clinical hypothesis. Although uncommon, incontinentia pigmenti should be taken into consideration as a possible differential diagnosis when vesiculobullous and verrucous lesions are present in childhood.

Estudio de las distrofias vitreorretinianas en población mexicana / Study of vitreoretinal dystrophies in a Mexican population

BACKGROUND: We undertook this study to demonstrate the incidence of vitreoretinal dystrophies in a Mexican population. METHODS: This was a retrospective, observational, descriptive, transverse study. We analyzed the files of patients treated at the Retina Department of a medical center for state employees (ISSSTE) from January 1991 to December 2006 to obtain the incidence of vitreoretinal dystrophies. RESULTS: We studied 36,300 patient files. We found an incidence of 0.008% for familial exudative vitreoretinal dystrophy, 0.008% for X-linked juvenile retinoschisis, 0.005% for Wagner disease and 0.005% for Goldmann-Favre disease. We present here a representative case of each type of dystrophy. CONCLUSIONS: Vitreoretinal dystrophies are uncommon diseases and are difficult to diagnose. Even though their incidence is low, the poor evolution to blindness requires identification of early signs in order to offer timely and opportune treatment.

Discrepancies in the laws on identifying foetal sex and terminating a pregnancy in India.

Laws that regulate the identification of a foetus and the termination of a pregnancy in India are shaped by their social context. The Medical Termination of Pregnancy Act, 1971, discriminates against unmarried women by not recognising that unwanted pregnancies in unmarried women could result in at least as much anguish and suffering as that experienced by married women. While the MTP Act permits the abortion of foetuses with disabilities, the Pre-conception and Pre-natal Diagnostic Techniques (Prohibition of Sex Selection) Act's ban on identifying the foetus's sex prevents the use of sex-detection to identify foetuses at high risk of sex-linked diseases.

Lissencephaly, abnormal genitalia and refractory epilepsy: case report of XLAG syndrome / Lisencefalia, genitália ambígua e epilepsia refratária: relato de caso da síndrome XLAG

INTRODUCTION: X-linked lissencephaly with ambiguous genitalia (XLAG) is a recently described genetic disorder caused by mutation in the aristaless-related homeobox (ARX) gene (Xp22.13). Patients present with lissencephaly, agenesis of the corpus callosum, refractory epilepsy of neonatal onset, acquired microcephaly and male genotype with ambiguous genitalia. CASE REPORT: Second child born to healthy nonconsanguineous parents, presented with seizures within the first hour of life that remained refractory to phenobarbital, phenytoin and midazolam. Examination identified microcephaly, axial hypotonia, pyramidal signs and ambiguous genitalia. EEG showed disorganized background activity and seizures starting at the right midtemporal, central and occipital regions. MRI showed diffuse pachygyria, moderate thickening of the cortex, enlarged ventricles, agenesis of the corpus callosum and septum pellucidum. Karyotype showed a 46,XY genotype. Additional findings were hypercalciuria, vesicoureteral reflux, patent ductus arteriosus and chronic diarrhea.

INTRODUÇÃO: Lisencefalia com genitália ambígua ligada ao X (XLAG) é doença genética recentemente descrita, causada por mutação no gene aristaless-related homeobox (ARX) (Xp22.13). Os pacientes apresentam lisencefalia, agenesia de corpo caloso, epilepsia refratária com início no período neonatal, microcefalia adquirida e genótipo masculino com genitália ambígua. RELATO DE CASO: Segundo filho de pais não-consangüíneos, apresentou crises na primeira hora de vida que permaneceram refratárias a fenobarbital, fenitoína e midazolam. Apresentava microcefalia, hipotonia axial, sinais de liberação piramidal e genitália ambígua. EEG demonstrou atividade de base desorganizada, crises convulsivas com início nas regiões temporal-média, central e occipital direitas. RNM demonstrou paquigiria difusa, moderado espessamento do córtex, ventrículos aumentados, agenesia de corpo caloso e septo pelúcido. Cariótipo evidenciou genótipo 46,XY. Achados adicionais foram: hipercalciúria, refluxo vésico-ureteral, ducto arterioso persistente e diarréia crônica.

Síndrome de McLeod: compromiso multisistémico asociado a neuroacantocitosis ligada al cromosoma X, en una familia chilena / McLeod syndrome: Multisystem involvement associated with neuroacanthocytosis linked to X chromosome. Report of two related cases

Neurological abnormalities associated with spiculated, "acanthocytic" red cells in blood have been described as neuroacanthocytosis. This is a heterogeneous group of conditions that can be clearly subdivided on the basis of recent genetic findings. The McLeod Syndrome, one of the core neuroacanthocytosis syndromes, is a rare X-linked disorder caused by mutations of the XK gene, an X-chromosomal gene of unknown function characterized by haemopoietic abnormalities and late-onset neurological and muscular defects. We report two Chilean brothers with the McLeod phenotype who showed important psychiatric features. The diagnosis may be elusive if the presence of acanthocytosis is not properly studied. We describe a method which allowed the diagnosis that unmasked acanthocytosis. Otherwise the condition could have remained undiagnosed as it had been for decades in this family. This syndrome must be considered when assessing a familial movement disorder, specially affecting males with relevant psychiatric features. A reliable test for acanthocytosis assessment is available.

Floppy infant caused by MTM1 mutation: a first genetically-confirmed X-linked myotubular myopathy patient in Thailand.

Floppy infant syndrome (FIS) refers to a condition wherein an infant manifests generalized hypotonia since birth or in early life. It is heterogeneous and can be caused by various central nervous system disorders, neuromuscular diseases and genetic disorders. X-linked myotubular myopathy (XMTM) is a progressive congenital myopathy morphologically characterized by the presence of centrally placed nuclei in numerous muscle fibers without any other particular pathological abnormalities. Patients are frequently born with floppiness and respiratory distress. The vast majority of patients carry a truncating or missense mutation in MTM1. The authors report here a full term male baby with clinicopathological features of XMTM. The diagnosis is validated by the finding of a c. 141-144delAGAA mutation ofMTM1. To the best of the authors' knowledge, the present case is the first genetically confirmed XMTM in Thailand. A brief review of various neuromuscular disorders causing floppy infant syndrome is also included.

De novo mutation causing X-linked hyper-IgM syndrome: a family study in Taiwan.

X-linked hyper-IgM syndrome (XHIM) is a rare primary immunodeficiency disorder caused by mutations of the gene encoding the CD40 ligand (CD40L). It is characterized by recurrent infections with markedly decreased serum IgG, IgA and IgE levels but normal or elevated IgM levels. We report the clinical manifestations and complete immune studies in the first family with molecularly proven XHIM in Taiwan. A 5-month-old boy presented with rapidly progressive pneumonia which responded poorly to antibiotics. High levels of IgM and very low levels of IgG, IgA, and IgE were noted in his plasma specimen: IgM, 128 mg/dl; IgG, 18 mg/dl; IgA, 4 mg/dl); IgE, 1 IU/ml. Whole blood flow cytometry when he was 21 months old showed that only a small percentage (0.48%) of his in vitro-activated CD4+ T cells expressed CD40L. When he was 3 years old, repeated flow cytometry showed essentially the same result (0.4%), compared with his father's CD40L expression of over 85%. The patient's mother had moderately decreased CD40L expression (74.4%). Hyper-IgM syndrome was confirmed by CD40L mutation analysis in the boy, which revealed a Lys 96 stop (nucleotide A307T) in exon 2 of CD40L, with a truncated protein resulting in the loss of the entire TNF domain. His mother was a carrier and apparently the individual in whom the mutation originated. Eleven other family members, including the patient's father, sister, and grandmother, and the mother's sisters and their children, all had normal results on CD40L mutation analysis. The patient has remained without significant bacterial infection on a regimen of monthly IVIG infusion and oral trimethoprim-sulfamethoxazole for Pneumocystis carinii pneumonia (PCP) prophylaxis, although he has had recurrent oral ulcers and neutropenia. Bone marrow transplantation is planned.