Homozygous mutations in LPIN2 are responsible for the syndrome of chronic recurrent multifocal osteomyelitis and congenital dyserythropoietic anaemia (Majeed syndrome)

BACKGROUND

Majeed syndrome is an autosomal recessive, autoinflammatory disorder characterised by chronic recurrent multifocal osteomyelitis and congenital dyserythropoietic anaemia. The objectives of this study were to map, identify, and characterise the Majeed syndrome causal gene and to speculate on its function and role in skin and bone inflammation.

METHODS

Six individuals with Majeed syndrome from two unrelated families were identified for this study. Homozygosity mapping and parametric linkage analysis were employed for the localisation of the gene responsible for Majeed syndrome. Direct sequencing was utilised for the identification of mutations within the genes contained in the region of linkage. Expression studies and in silico characterisation of the identified causal gene and its protein were carried out.

RESULTS

The phenotype of Majeed syndrome includes inflammation of the bone and skin, recurrent fevers, and dyserythropoietic anaemia. The clinical picture of the six affected individuals is briefly reviewed. The gene was mapped to a 5.5 cM interval (1.8 Mb) on chromosome 18p. Examination of genes in this interval led to the identification of homozygous mutations in LPIN2 in affected individuals from the two families. LPIN2 was found to be expressed in almost all tissues. The function of LPIN2 and its role in inflammation remains unknown.

CONCLUSIONS

We conclude that homozygous mutations in LPIN2 result in Majeed syndrome. Understanding the aberrant immune response in this condition will shed light on the aetiology of other inflammatory disorders of multifactorial aetiology including isolated chronic recurrent multifocal osteomyelitis, Sweet syndrome, and psoriasis.

Risk factors for childhood epilepsy: a case-control study from Irbid, Jordan

OBJECTIVE

The goal of this case-control study is to identify the significance of certain risk factors for epilepsy in a population of epileptic children in Northern Jordan. The risk factors examined are febrile convulsions, head trauma, central nervous system infections, abnormal perinatal history, family history and parental consanguinity.

METHODOLOGY

We designed a case-control study for patients attending the outpatient neurology clinic of Princess Rahma Teaching Hospital in Irbid, Jordan during a 7-month period. Controls were selected, matched for age and sex, from a group of non-epileptic patients attending the general paediatrics outpatient clinic in the same hospital and during the same period. Data about the investigated risk factors were obtained by personal interview and review of the medical records and were analysed statistically for significance.

RESULTS

The total number of participants was 200 patients and controls each. History of febrile convulsions, head trauma, abnormal perinatal history and family history showed a statistically significant increase risk for developing epilepsy. Central nervous system infections and parental consanguinity did not add to the risk of developing epilepsy.

CONCLUSION

Positive family history for epilepsy, head trauma, febrile convulsions and abnormal perinatal history were shown to have a statistically significant association with epilepsy in patients attending Princess Rahma Teaching Hospital in Northern Jordan. Although consanguinity is widely practised in Jordan, it appears that it does not increase the risk of epilepsy probably due to the small contribution of monogenic recessive epilepsies to the population with epilepsy.

The syndrome of chronic recurrent multifocal osteomyelitis and congenital dyserythropoietic anaemia. Report of a new family and a review

A new autosomal recessive syndrome of chronic recurrent multifocal osteomyelitis (CRMO) and congenital dyserythropoietic anaemia (CDA) with microcytosis has recently been described in four children (two sibships) of one consangineous Arab family. In this report, we describe the clinical features and course of the syndrome of CRMO and CDA in two additional patients (one sibship) from another consanguineous Arab family and review the literature. The two patients (brother and sister), the products of a consanguineous marriage, developed the syndrome at an early age of 3 weeks and 2 months respectively. The diagnosis of CRMO was confirmed by radiological and technetium isotope bone scans. Bone marrow studies confirmed the diagnosis of CDA. Peripheral blood films showed hypochromia and microcytosis. The sites involved by CRMO were periarticular, mainly around the elbow, knee, wrist and small joints of the hand. The brother is now 21 years old and the sister 3.5 years old and CRMO is still active with frequent relapses. The brother developed flexion deformities at the age of 13 years. Both patients failed to thrive; weight and height were below the 5th percentile.

CONCLUSION

This is the second report of the syndrome of chronic recurrent multifocal osteomyelitis and microcytic congenital dyserythropoietic anaemia, confirming it as a clinical entity, inherited as an autosomal recessive trait. The disease is characterised by an early onset, long clinical course of remissions and relapses, and seems to be different from the sporadic form of chronic recurrent multifocal osteomyelitis.

Familial disorder of sex determination in seven individuals from three related sibships

In humans, the sex of an individual is determined by the Y-chromosome-related SRY gene, which causes the differentiation of the undifferentiated gonads into testicular tissue. True hermaphrodites without a Y chromosome and XX males represent a sex determination error in which testicular tissue develops despite the absence of the SRY gene. Familial forms of XX true hermaphrodites and XX males exist in the literature, which also contains the two forms co-existing in the same family. In this report, we present a large family with seven affected individuals with phenotypes ranging from XX male to XX true hermaphrodite with predominance of female characteristics. We suggest that XX maleness and XX true hermaphroditism represent a continuum of the same disorder. We speculate on the mode of inheritance of this disorder in this particular family.

Mutations in the CCN gene family member WISP3 cause progressive pseudorheumatoid dysplasia

Members of the CCN (for CTGF, cyr61/cef10, nov) gene family encode cysteine-rich secreted proteins with roles in cell growth and differentiation. Cell-specific and tissue-specific differences in the expression and function of different CCN family members suggest they have non-redundant roles. Using a positional-candidate approach, we found that mutations in the CCN family member WISP3 are associated with the autosomal recessive skeletal disorder progressive pseudorheumatoid dysplasia (PPD; MIM 208230). PPD is an autosomal recessive disorder that may be initially misdiagnosed as juvenile rheumatoid arthritis. Its population incidence has been estimated at 1 per million in the United Kingdom, but it is likely to be higher in the Middle East and Gulf States. Affected individuals are asymptomatic in early childhood. Signs and symptoms of disease typically develop between three and eight years of age. Clinically and radiographically, patients experience continued cartilage loss and destructive bone changes as they age, in several instances necessitating joint replacement surgery by the third decade of life. Extraskeletal manifestations have not been reported in PPD. Cartilage appears to be the primary affected tissue, and in one patient, a biopsy of the iliac crest revealed abnormal nests of chondrocytes and loss of normal cell columnar organization in growth zones. We have identified nine different WISP3 mutations in unrelated, affected individuals, indicating that the gene is essential for normal post-natal skeletal growth and cartilage homeostasis.

The clinical spectrum of Henoch-Schönlein purpura in infants and young children

Henoch-Schönlein purpura is a common cause of childhood vasculitis. The rarity of the disease under 2 years of age has been the subject of few reports. We present the clinical spectrum of Henoch-Schönlein purpura in 12 children younger than 2 years of age at presentation. The median age at presentation was 11 months. The purpuric skin rash was present in all patients and involved the face in 10 of them. While oedema was a prominent feature in all of our patients only one third had involvement of the kidneys, gastro-intestinal tract or joints. All patients recovered completely after a mean duration of follow up of 10.6 months (range 2-39 months).

CONCLUSION

Henoch-Schönlein purpura under the age of 2 years is characterized clinically by oedema and a purpuric skin rash which frequently affects the face. Involvement of the joints, kidneys and gastro-intestinal tract is uncommon and the prognosis is excellent. The clinical spectrum in this age group is a continuation with that of Henoch-Schönlein purpura in older children suggesting a nosological entity.