Hereditary lymphopenic agammaglobulinemia associated with a distinctive form of short-limbed dwarfism and ectodermal dysplasia

EXTL3 mutations cause skeletal dysplasia, immune deficiency, and developmental delay

Volpi et al. demonstrate that hypomorphic EXTL3 mutations cause abnormalities of heparan sulfate composition, affect signaling in response to growth factors and cytokines, and perturb thymopoiesis, resulting in a novel genetic disease associating skeletal dysplasia, T cell immunodeficiency, and neurodevelopmental delay.

We studied three patients with severe skeletal dysplasia, T cell immunodeficiency, and developmental delay. Whole-exome sequencing revealed homozygous missense mutations affecting exostosin-like 3 (EXTL3), a glycosyltransferase involved in heparan sulfate (HS) biosynthesis. Patient-derived fibroblasts showed abnormal HS composition and altered fibroblast growth factor 2 signaling, which was rescued by overexpression of wild-type EXTL3 cDNA. Interleukin-2–mediated STAT5 phosphorylation in patients’ lymphocytes was markedly reduced. Interbreeding of the extl3-mutant zebrafish (box) with Tg(rag2:green fluorescent protein) transgenic zebrafish revealed defective thymopoiesis, which was rescued by injection of wild-type human EXTL3 RNA. Targeted differentiation of patient-derived induced pluripotent stem cells showed a reduced expansion of lymphohematopoietic progenitor cells and defects of thymic epithelial progenitor cell differentiation. These data identify EXTL3 mutations as a novel cause of severe immune deficiency with skeletal dysplasia and developmental delay and underline a crucial role of HS in thymopoiesis and skeletal and brain development.

Phenotypic variations of cartilage hair hypoplasia: granulomatous skin inflammation and severe T cell immunodeficiency as initial clinical presentation in otherwise well child with short stature

We report a child with short stature since birth who was otherwise well, presenting at 2.8 years with progressive granulomatous skin lesions when diagnosed with severe T cell immunodeficiency. When previously investigated for short stature, and at the time of current investigations, she had no radiological skeletal features characteristics for cartilage hair hypoplasia, but we found a disease causing RMRP (RNase mitochondrial RNA processing endoribonuclease) gene mutation. Whilst search for HLA matched unrelated donor for haematopoietic stem cell transplantation (HSCT) was underway, she developed rapidly progressive EBV-related lymphoproliferative disorder requiring laparotomy and small bowel resection, and was treated with anti-B cell monoclonal antibody and eventually curative allogeneic HSCT. Screening for RMRP gene mutations should be part of immunological evaluation of patients with ‘severe and/or combined’ T cell immunodeficiency of unknown origin, especially when associated with short stature and regardless of presence or absence of radiological skeletal features.

A unique presentation of immuno-osseous dysplasia

The immuno-osseous dysplasias are a rare group of conditions in which short-limbed dwarfism is associated with an immune defect. The best known of these is cartilage hair hypoplasia. However, several reports of other distinct conditions exist, which have been arbitrarily classified on the basis of the immune defect. We present a child with a previously unreported combination of immune and skeletal abnormalities in whom there was an unusual and distinctive skin appearance associated with defective cutaneous elastic fibers. These cutaneous features suggest a unifying link with other immuno-osseous dysplasia but the combination of immune and skeletal defects exposes weaknesses in the current method of classification.

Human disease resulting from gene mutations that interfere with appropriate nuclear factor-kappaB activation

The nuclear factor (NF)-kappaB family of transcription factors serves vital roles in a wide array of cell functions. An increasing number of human genetic lesions that result in defined disease entities are linked to inappropriate activation of NF-kappaB. The resulting aberrant NF-kappaB function can lead to cellular defects that ultimately impair normal developmental processes, host immune defenses, or both. Molecular defects that lie upstream in cell-signaling pathways and rely upon NF-kappaB activation tend to give a more specific phenotype, whereas those closer to the actual NF-kappaB proteins have broader defects. A detailed study of these diseases can provide insight into the biochemistry of NF-kappaB activation as well as the role of NF-kappaB in human health.

Syndromic immunodeficiencies: genetic syndromes associated with immune abnormalities

In syndromic immunodeficiencies, clinical features not directly associated with the immune defect are prominent. Patients may present with either infectious complications or extra-immune medical issues. In addition to the immunologic abnormality, a wide range of organ systems may be affected. Patients may present with disturbances in skeletal, neurologic, dermatologic, or gastrointestinal function or development. These conditions can be caused by developmental abnormalities, chromosomal aberrations, metabolic disorders, or teratogens. For a number of these conditions, recent advances have resulted in an enhanced understanding of their genetic basis. The finding of immune deficits in a number of defined syndromes with congenital anomalies suggests that an underlying genetic syndrome should be considered in those patients in whom a significant non-immune feature is present.

A novel developmental and immunodeficiency syndrome associated with intrauterine growth retardation and a lack of natural killer cells

OBJECTIVE

To describe a novel syndrome characterized by severe prenatal and postnatal growth failure, mild skeletal and facial abnormalities, and primary immunodeficiency.

DESIGN

The syndrome was observed in 2 sisters. The elder child died of cytomegalovirus infection when she was 18 months old, whereas the younger sister is doing well at 5 years old. We report here clinical, hematologic, and immunologic data for both sisters and compare them with all known inherited disorders with similar clinical or immunologic features.

RESULTS

The immune defect consists of a lack of detectable natural killer cells and small numbers of CD8 alphabeta T cells and polymorphonuclear neutrophils. This is the first report of prenatal and postnatal growth failure associated with mild skeletal and facial abnormalities and primary immunodeficiency.

CONCLUSION

This novel syndrome probably is caused by an autosomal recessive gene defect impairing both intrauterine growth and natural killer cell development. The identification of other kindreds with this syndrome would facilitate the search for its genetic basis.

Distinctive metaphyseal chondrodysplasia with severe distal radius and ulna involvement (upper extremity mesomelia) and normal height

Metaphyseal chondrodysplasias (MCD) are skeletal disorders characterized by metaphyseal irregularities and, usually, by short stature. In MCD, wide heterogeneity exists with regard to clinical and radiological changes. We report on a patient with clinical and radiological findings of MCD who had coxa valga and normal height with metaphyseal involvement of the long bones. The short radii and ulnae showed a very severe change in their distal metaphyses, leading to mesomelic shortening confined to the upper limbs. Hematological, ophthalmological, and hearing examinations were normal. This type of MCD appears to represent a yet undescribed syndrome.

A novel syndrome of combined immunodeficiency, autoimmunity and spondylometaphyseal dysplasia

We describe here four patients who appear to have similar clinical and immunological features which constitute a novel syndrome. The patients present with short stature owing to spondylometaphyseal dysplasia and with severe infections as the result of a combined humoral and cellular immune deficiency. Presumably because of dysregulation of the immune system, all patients also developed autoimmune manifestations.

Mammalian twisted gastrulation is essential for skeleto-lymphogenesis

Dorsoventral patterning depends on the local concentrations of the morphogens. Twisted gastrulation (TSG) regulates the extracellular availability of a mesoderm inducer, bone morphogenetic protein 4 (BMP-4). However, TSG function in vivo is still unclear. We isolated a TSG cDNA as a secreted molecule from the mouse aorta-gonad-mesonephros region. Here we show that TSG-deficient mice were born healthy, but more than half of the neonatal pups showed severe growth retardation shortly after birth and displayed dwarfism with delayed endochondral ossification and lymphopenia, followed by death within a month. TSG-deficient thymus was atrophic, and phosphorylation of SMAD1 was augmented in the thymocytes, suggesting enhanced BMP-4 signaling in the thymus. Since BMP-4 promotes skeletogenesis and inhibits thymus development, our findings suggest that TSG acts as both a BMP-4 agonist in skeletogenesis and a BMP-4 antagonist in T-cell development. Although lymphopenia in TSG-deficient mice would partly be ascribed to systemic effects of runtiness and wasting, our findings may also provide a clue for understanding the pathogenesis of human dwarfism with combined immunodeficiency.

Antibody deficiency, growth retardation, spondyloepiphyseal dysplasia and retinal dystrophy: a novel syndrome

The clinical and laboratory combination of recurrent infections due to antibody deficiency, spondyloepiphyseal dysplasia, growth retardation and retinal dystrophy is novel. Four patients with strikingly similar phenotypes from three different families of diverse genetic backgrounds are described, suggesting a similar underlying genotype. Increased awareness of this syndrome will hopefully lead to the description of a larger number of affected individuals, which ultimately might be critical for its genetic characterization.

Spondylo-mesomelic-acrodysplasia with joint dislocations and severe combined immunodeficiency: a newly recognised immuno-osseous dysplasia

A newborn girl is described with an association of spondylo-acrodysplasia, mild short limbed dwarfism without significant metaphyseal changes, joint dislocations, and severe immune system dysfunction. This association is distinct from other known immuno-osseous dysplasias, including Schimke dysplasia, ADA deficiency with osseous changes, and Omenn phenotype with short limbed dwarfism.

Immunodeficiency as a component of recognizable syndromes

Immunodeficiency occurs in numerous genetic syndromes. While it is the dominant manifestation in primary immunodeficiencies, immune deficits may also be seen in a variety of other recognizable syndromes. Immunodeficiency has been reported in 64 such conditions, adding to the 45 recognized primary immunodeficiencies. These uncommon syndromes with immune defects can present with: (a) growth deficiency (11 syndromes with disproportionate or proportionate short stature), (b) specific organ system dysfunction (18 with gastrointestinal, dermatologic, or neurologic abnormalities), (c) inborn errors of metabolism (13), (d) miscellaneous anomalies (10), or (e) chromosome anomalies (12). In most of the disorders, only some of the affected patients have immune defects. However, in 27 syndromes, immunodeficiency is a constant finding. We briefly review the clinical manifestations of each syndrome and delineate the specific associated immune defects. In most syndromes, the connection between the immune and other defects is unknown. Recognition of these conditions involving both the immune and other organ systems may facilitate accurate diagnosis and management as well as yield information regarding genes critical for the development of the involved systems.

Acquired ichthyosis in concomitant HIV-1 and HTLV-II infection: a new association with intravenous drug abuse

BACKGROUND

Papulosquamous eruptions are common in HIV-1-infected patients. Acquired ichthyosis may occur after profound T-cell depletion. Intravenous drug users infected with HIV-1 can be coinfected with human lymphotropic virus II (HTLV-II).

OBJECTIVE

We examined the relation between acquired ichthyosis and concomitant infection with HIV-1 and HTLV-II in intravenous drug users.

METHODS

We examined 184 male and female HIV-1-positive intravenous drug users for acquired ichthyosis. Enzyme-linked immunosorbent assay was used to screen these patients for antibody to HTLV-I/II. Western blot, viral isolation, and the polymerase chain reaction were used to confirm that serologic responses were from HTLV-II and not HTLV-I.

RESULTS

Acquired ichthyosis occurred in 6.3% of white, 16.4% of Hispanic, and 21.7% of black patients. It occurred only after profound helper T-cell depletion, in association with increasing age, and with concomitant infection with HTLV-II (22.2% vs. 6.8% in HIV-1 singly infected patients [p < 0.038]).

CONCLUSION

Acquired ichthyosis may be a marker of concomitant infection with HIV-1 and HTLV-II in intravenous drug users and occurs after profound helper T-cell depletion.

Schimke immuno-osseous dysplasia: a newly recognized multisystem disease

On the basis of five cases personally observed and one previously reported, we describe a disorder characterized by skeletal dysplasia, rapidly progressive nephropathy, episodes of lymphopenia, and pigmentary skin changes. Defects of T-cell function were compatible with an autoimmune process. The disorder is probably of genetic origin and inherited as an autosomal recessive trait.

Short stature/short limb skeletal dysplasia with severe combined immunodeficiency and bowing of the femora: report of two patients and review

We report two patients with severe combined immunodeficiency and short stature/short limb skeletal dysplasia. Case 1 presented at birth with rhizomelic shortening of the extremities and bowing of the femora. She developed clinical signs of severe combined immunodeficiency at 13 months and died at 21 months. Case 2 had severe prenatal shortening and bowing of the extremities and a small, malformed chest. Symptoms of severe combined immunodeficiency and severe failure to thrive developed soon after birth and she died at 5 months. The diagnosis of severe combined immunodeficiency in our patients was based on their clinical course and necropsy findings, supported in case 1 by the results of immune function tests. The results of investigation of immune function (immunoglobulins, lymphocyte subpopulations, lymphocyte function) are very variable in this syndrome as in other variants of severe combined immunodeficiency. Bone histopathology in both patients showed grossly irregular costochondral junctions, but normal transition of proliferating to hypertrophic chondrocytes. These cases belong to early lethal type 1 short limb skeletal dysplasia with severe combined immunodeficiency. Review of previously published cases with severe combined immunodeficiency and well documented skeletal findings show eight patients with prenatal onset of bowing and shortening of the extremities and metaphyseal abnormalities. These include two sib pairs concordant for the skeletal changes. In these cases, adenosine deaminase levels were not reported. An additional four published cases with associated adenosine deaminase deficiency had only mild metaphyseal abnormalities, but subsequently showed no linear growth.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital atrichia with nail dystrophy, abnormal facies, and retarded psychomotor development in two siblings: a new autosomal recessive syndrome?

We cared for two sisters, ages 3 and 4 years, who suffered from congenital atrichia. Scalp biopsies performed on both children revealed a marked atrophy of hair follicles with rudimentary hair shafts. The absence of peribulbar infiltrates ruled out alopecia areata. Dystrophy of all nails, distinctive facies, retarded psychomotor development, and a delay in speaking were additional symptoms. The unique combination of findings excludes well-established syndromes such as atrichia with papular lesions, GAPO syndrome, and dominant hidrotic ectodermal dysplasia, as well as X-linked hypohidrotic ectodermal dysplasia. We therefore conclude that we may be dealing with a new genetic entity. The occurrence of the disorder in two siblings with unaffected parents suggests an autosomal recessive mode of inheritance.

Biochemical, morphological and immunological findings in a patient with a cutis laxa-associated inborn disorder (De Barsy syndrome)

Clinical symptoms of a male infant are described and compared with cases now classified as the De Barsy syndrome, a distinct disorder related to cutis laxa. Morphologically, elastic fibres in skin were frayed and reduced in number and density. The collagen fibril network was normal. Biochemical studies on collagen metabolism in a skin specimen and in cultured skin fibroblasts showed a normal amino acid content and a normal electrophoretic pattern of collagen constituents. The chemotactic migration of cultured fibroblasts was diminished when compared with fibroblasts from donors of different age groups. Immunological investigations revealed an imparied granulocyte function.

Microcephaly, short stature, and developmental delay associated with a chemotactic defect and transient hypogammaglobulinaemia in two brothers

Two brothers presented with unusual facial features, microcephaly, developmental delay, and severe postnatal growth retardation. They both developed eczema in infancy and have had recurrent infections. Additional physical findings in both boys included hypogonadism, flexion contractures, hypoplastic patellae, and scoliosis. Their facial similarity was striking with sloping foreheads, beaked noses, large, protruding ears, and micrognathia. Low levels of serum gammaglobulins and defective chemotaxis were present in both boys in infancy. The hypogammaglobulinaemia was transient and improved, reaching normal levels by 3 1/2 years and 15 months, respectively. Defective chemotaxis and recurrent infections have persisted to the present. Both parents were normal. The mode of inheritance was not clear, as both X linked and autosomal recessive patterns were possible. Although patients with congenital malformations who also had immunodeficiency have previously been reported, immune system abnormalities, especially those of a transient nature, may frequently go unrecognised.

Human posttransfusion graft-versus-host disease

Graft-versus-host disease (GVDH) follows blood product transfusions in patients with deficient cell-mediated immunity. The rate of mortality in this adverse effect of blood transfusions is between 90 and 100%. The historical; clinical and pathologic; and mechanism of acute and chronic GVHD are presented. The patients at risk, the clinical and pathologic features of posttransfusion GVDH have been presented in hopes that, with increased awareness of this usually fatal complication, clinicians and transfusion therapists may more intelligently advise and select patients who may need lymphocyte-poor or irradiated blood products and may recognize the syndrome earlier.

Graft-versus-host reaction following blood product transfusion

The observation of graft-versus-host (GVH) reaction after platelet transfusion in a patient with Hodgkin's disease led us to analyze 38 reported cases in the literature, to outline prognostic factors and to characterize patients at risk. Overall mortality was 68 percent. It was higher among children (76 percent) than among adults (62 percent), and among patients with Hodgkin's disease and immune deficiency syndromes (88 percent) than among those with leukemias (23 percent, p less than 0.005). Following blood transfusions from normal donors, mortality was higher (88 percent) than after transfusions from donors with chronic myelocytic leukemia (25 percent, p less than 0.05). Minimal lymphocyte doses necessary to cause GVH reaction are in excess of 10(7)/kg. Adults seem more resistant to homografts than do children, and the host's cellular immune status is of major prognostic importance. Lymphocytes from donors with chronic myelocytic leukemia may be deficient, and after a threshold dose, the number of lymphocytes transfused does not correlate with clinical outcome. Effective prophylactic measures do exist for this complication but satisfactory therapy does not.

T system immunodeficiencies in infancy and childhood

Some problems concerning the diseases due to deficiencies of the T immune system in infancy and childhood are reviewed. The relationships between SCID and Nezelof syndrome and the pathogenesis of this group of diseases are particularly discussed.

An unusual case of metaphyseal chondrodysplasia with an abnormal perilacunar matrix associated with agranulocytosis and hypoplasia of the thymus

We report herein an unusual skeletal dysplasia in a 6-month-old boy characterized by metaphyseal dysplasia associated with agranulocytosis and hypoplasia of the thymus. A radiological survey revealed generalized metaphyseal abnormalities showing widening and increased density. Pathological changes in the chondro-osseous tissues were unusual and distinctive. There was widespread evidence of abnormal chondrocytes with an abnormal perilacunar matrix containing a PAS-positive, diastase resistant substance. Chondrocyte maturation and regular columnar arrangement were absent in most growth plates with only scattered ball-like nests of chrondrocytes showing incomplete maturation. This case is a newly described form of osteochondrodysplasia.

An autosomal recessive ectodermal dysplasia syndrome of hypotrichosis, onychodysplasia, hyperkeratosis, kyphoscoliosis, catartact, and other manifestations

We describe a 20-year-old woman with generalized trichodysplasia, dry skin with scaling, hyperchromic spots on limbs, hyperkeratosis (particularly intense on soles), dermatoglyphic abnormalities, onychodysplasia, shortness of stature, kyphoscoliosis, unusual facial appearance, minor malformations of limbs, bilateral nuclear cataract, narrow palpebral fissures, entropion, trichiasis, etc. The condition is probably due to an autosomal recessive gene. The patient is the only affected member in a sibship of four whose parents are second cousins.

The chondro-osseous dysplasia of adenosine deaminase deficiency with severe combined immunodeficiency

Three children, two of them siblings, with severe combined immunodeficiency and adenosine deaminase deficiency died within the first six months of life from the complications of acute bacterial infections. Subtle radiographic abnormalities were seen at the costochondral junctions, at the apophysis of the iliac bones, and in the vertebral bodies. At autopsy, the thymus showed evidence of early differentiation and, in one instance, aborted Hassall's corpuscles. Histologic study of the bone disclosed lack of organized cartilage columnar formation, large lacuni containing hypertrophied cells, and lack of trabecular formation with uninterrupted areas of calcified cartilage. These changes are distinctly different from those observed in the metaphyseal chondrodysplasias or in other chondrodystrophies.