What Is Czech Dysplasia?
Czech dysplasia is an inherited autosomal dominant disease that is characterized by joint pain and abnormal bone development. Usually, the patients of Czech dysplasia exhibit early-onset osteoarthritis that is rapidly progressive, brachydactyly (a condition that causes shortening of the fingers and toes as compared to other parts of the body) of the third and fourth toes, and defective bone synthesis. The symptoms usually appear in adolescence or late childhood.
The joints present in the hip region, knees, shoulders, and spinal cord are chiefly affected and cause impairment in joint mobility. Patients suffering from Czech dysplasia usually have smaller bones in the third and fourth toes thereby making their remaining toes appear more extended than usual. Flattening of bones of the spine (platyspondyly) or abnormal curvature of the spinal cord, such as abnormally rounded spinal bone that is also curved to the side (kyphoscoliosis) is also seen in the affected patients. Some patients affected with Czech dysplasia also suffer from progressive hearing loss.
This disorder was named Czech dysplasia because most families affected with this condition derive their origin from or have ancestors in the Czech Republic.
What Are the Causes of Czech Dysplasia?
Czech dysplasia occurs due to a genetic mutation in the gene collagen type II alpha 1 chain (COL2A1). The collagen type II alpha 1 chain gene is responsible for providing important information for synthesizing proteins that form type II collagen. Type II collagen is prominently found in the transparent gel matrix that fills the vitreous chamber of the eyeball and in cartilage. Cartilage is a resilient and flexible tissue that the skeleton comprises during the early formative years of skeletal development. Most of this laid cartilage is later transformed into bone, except for the cartilage that is covering and protecting the ends of bones and occurs in the nose and external ears. Type II collagen is primarily crucial for the normal synthesis of bones and other granulation tissue that forms the supportive framework of the body. Genetic mutations in the collagen type II alpha 1 chain gene disrupt the assembly of type II collagen molecules thereby preventing proper bone development and proper synthesis of other connective tissues of the body. These genetic mutations are inherited in an autosomal dominant pattern.
What Is the Frequency of Czech Dysplasia?
The frequency of this disorder is rare. The prevalence of Czech dysplasia is not known. Only eleven families have been found to be affected by this disorder. Most of the affected people reside in the Czech Republic.
What Is the Inheritance Pattern of Czech Dysplasia?
The inheritance pattern of Czech dysplasia is an autosomal dominant type which means in each cell only a single copy of the mutated collagen type II alpha 1 chain gene is sufficient to cause the disease.
All known patients affected with this condition inherited this mutated gene from either of the parents affected by this disorder.
What Are the Other Synonyms of Czech Dysplasia?
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Czech dysplasia, metatarsal type.
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Progressive pseudo-rheumatoid dysplasia with hypoplastic toes.
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Spondyloarthropathy with brachydactyly of third and fourth toes.
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Spondyloepiphyseal dysplasia with metatarsal shortening.
What Are the Signs and Symptoms of Czech Dysplasia?
Individuals suffering from this condition exhibit the symptom of progressive pseudo-rheumatoid arthritis (a joint disorder that worsens with time and is characterized by degeneration of the articular cartilage present between the bones)in early childhood. Along with it, variable congenital defects in the vertebrae and congenital agenesis of the metatarsal bones of the third and fourth toes. Prominently broad knees and a depressed bone of the nasal bridge are the characteristic features of this condition. Pain and rigidity in the joints are also commonly seen in a few individuals. Joint pain occasionally depends on the changes in weather.
What Are the Radiographic Features of Czech Dysplasia?
The radiographic features include shortening of the metacarpal and metatarsal bones, decreased intervertebral spacing, and osteochondromatosis (a condition where the cartilage is developed by the process of metaplasia of the connective tissue cells).
How Is the Diagnosis of Czech Dysplasia Made?
The diagnosis of this disorder depends on the medical history and a thorough physical examination. However, it is quite challenging to diagnose the disease in early childhood. Therefore, skeletal radiographs showing platyspondyly (flattened spinal bones) and brachydactyly (shortened metatarsals and metacarpals of the third and fourth toes) may help in establishing the diagnosis. The broad metatarsals and phalanges in the bones of the toes, which are usually seen on both the child’s and the parent’s radiographs may further assist in diagnosing the condition.
The skeletal radiographs of either parent might reveal decreased joint space in the upper and lower extremities, broad metatarsal and phalangeal bone in the large toe of the foot, shoulder osteochondromatosis, flattened spinal bone, and Schmorl’s nodes in the spine.
A whole exome sequencing test can also be performed to trace one’s ancestral (family) roots. Here, the deoxyribonucleic acid is extracted from the monocytes in the peripheral blood and then coagulated for collection and evaluation.
What Is the Differential Diagnosis of Czech Dysplasia?
The differential diagnosis of Czech dysplasia is spondylo-epiphyseal dysplasias (SED) and autosomal dominant disorder spondyloarthropathy (ADSA). In spondylo-epiphyseal dysplasias, the legs are often more severely inflicted than the hands but none of the spondylo-epiphyseal dysplasias shows skeletal agenesis of the toes.
What Is the Treatment of Czech Dysplasia?
Treatment is usually symptomatic. Based on the symptoms, the treatment is provided:
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The brachydactyly (shortening of the metatarsals) of the third and fourth toes can be surgically corrected through metatarsal lengthening surgery.
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No effective treatment is available for platyspondyly.
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Pseudo-rheumatoid arthritis and extremely severe pain can be medically treated with drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs).
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Joint arthroplasty (an artificial prosthesis to restore the function of the joints) can also be performed to improve the condition.
Conclusion:
Czech dysplasia is a rare, hereditary joint and bone disorder characterized by skeletal deformities and joint pain. Early screening of the disorder along with symptomatic treatment and genetic counseling for the family prevents progressive damage to the bones and joints of the patient and provides relief to the affected individual.
