Spondyloepiphyseal dysplasia with nephrotic syndrome (Schimke immunoosseous dysplasia)

Total Knee Arthroplasty in Spondyloepiphyseal Dysplasia with Irreducible Congenital Dislocation of the Patella: Case Report and Literature Review

Background

Spondyloepiphyseal dysplasia is the clinical term applied to a group of rare genetic disorders with primary involvement of the vertebrae and epiphyses, predisposing the afflicted individuals toward the premature development of osteoarthritis. There are few reports concerning joint replacement therapy in these patients, particularly describing the role of total hip arthroplasty. In this report, we describe the anatomical and technical aspects of spondyloepiphyseal dysplasia that must be considered during surgical planning and performance of total knee arthroplasty.

Case Presentation

A 49-year old woman with a history of spondyloepiphyseal dysplasia suffered from severe osteoarthritis of the knee and irreducible congenital dislocation of the patella. After careful preoperative evaluations and planning, the knee joint deformity was solved by knee joint replacement with realignment of the extensor mechanism using quadricepsplasty. After 2 years of surgery, the patient showed no pain and was able to walk with the help of elbow crutches. The Hospital for Special Surgery knee score increased from preoperative 51 points to 85 points during the final follow-up. The postoperative range of motion increased to final flexion of 0–115°.

Conclusion

The advances made so far in the medical care for patients with skeletal dysplasia have improved their overall survival during adulthood. The case report described herein demonstrates the numerous challenges and technical aspects of a successful total knee arthroplasty in cases of spondyloepiphyseal dysplasia, highlighting the need to consider skeletal and soft tissue abnormalities of skeletal dysplasia during the planning and performance of joint replacement surgery.

SMARCAL1 mutations: a cause of prepubertal idiopathic steroid-resistant nephrotic syndrome

Schimke immuno-osseous dysplasia (SIOD) is a rare autosomal-recessive multisystem disorder with disproportionate growth failure, impaired T cell function, and steroid-resistant nephrotic syndrome. Recently, we presented the typical anthropometric features of SIOD. We now present data on two siblings who were initially classified as suffering from familial steroid-resistant nephrotic syndrome of unknown genetic origin. Apart from growth failure, no syndrome-specific symptoms were found until the age of 10 y. However, serial anthropometric examinations showed the development of a SIOD-like pattern with a decreased ratio of trunk to leg length in early adolescence. The growth pattern was significantly different from that seen in children with chronic renal failure of other origins. In prepuberty the siblings had proportionate short stature but developed disproportion only during adolescence. Molecular genetic analysis revealed compound heterozygosity for a known and a new mutation in the SMARCAL1 gene.

CONCLUSION

the disease spectrum associated with SMARCAL1 mutations includes previously undescribed milder phenotypes that may be clinically overlooked, particularly before puberty. Serial anthropometric assessment can eventually identify patients with a growth pattern similar to that of SIOD. These patients should be tested for SMARCAL1 mutations to avoid overtreatment with immunosuppressive agents.

Schimke versus non-Schimke chronic kidney disease: an anthropometric approach

Schimke-immuno-osseous dysplasia is a rare autosomal-recessive multisystem disorder with the main clinical features of disproportionate growth deficiency, defective cellular immunity, and progressive renal disease. It is caused by mutations of SMARCAL1, a gene encoding a putative chromatin remodeling protein of unknown function. Because a detailed description of the clinical features is an essential first step in elucidating the function of SMARCAL1, we present the first detailed anthropometric data for Schimke-immuno-osseous dysplasia patients. By comprehensive anthropometric examination (28 parameters) of 8 patients (3 females) with the typical findings of Schimke-immuno-osseous dysplasia (mean age: 14.8 years; range: 4.9-30.5 years) and 304 patients (117 females) with congenital and hereditary chronic kidney disease (mean age: 10.7 +/- 4.8 years; range: 3-21.8 years), we show that Schimke-immuno-osseous dysplasia patients differ significantly from those with other forms of chronic kidney disease. z scores were calculated with reference limits derived from 5155 healthy children (2591 females) aged 3 to 18 years. The key finding was that, in the latter group, median leg length was significantly more reduced than sitting height, whereas in Schimke-immuno-osseous dysplasia patients, the reduction of sitting height was significantly more pronounced than for leg length. Therefore, the ratio of sitting height/leg length might be a simple tool for the clinician to distinguish Schimke-immuno-osseous dysplasia from other chronic kidney disease patients. Schimke-immuno-osseous dysplasia is very likely if this ratio is < 0.83. However, other forms of chronic kidney disease have to be discussed in case of a ratio > 1.01.

Schimke immunoosseous dysplasia complicated by moyamoya phenomenon

Schimke immunoosseous dysplasia (SID) is an autosomal recessive spondyloepiphyseal dysplasia that was first described by Schimke et al. [1971: Lancet 2:1088-1089]. It is associated with premature arteriosclerosis and cerebral ischemia; however, the cerebral vascular abnormalities causing ischemia have not been described [Spranger et al., 1991: J Pediatr 119:64-72; Ehrich et al., 1995: Clin Nephrol 43:89-95]. Based on magnetic resonance angiography (MRA) and magnetic resonance venography (MRV), we now report on 2 girls with SID who have cerebral ischemia associated with moyamoya phenomenon. In addition, one patient also has an absent or occluded left transverse sinus and diffuse aortic narrowing. This is the first characterization of the cerebral vascular abnormality found in SID and raises the possibility that cerebral moyamoya may represent another major manifestation of the underlying genetic defect in SID.