Conradi Hunermann Syndrome

What is Conradi Hunermann Syndrome?

Genetically heterogeneous malfunctioning is the hallmark of the Conradi hunermann syndrome.  X-linked dominant trait plays a is key role in the development of the conradi hunermann syndrome. Defective calcium accumulation in the skeletal system is the characteristic feature of the  Conradi hunermann syndrome. The incidence rate is quite high in female in comparison to male, the ratio is denoted as 36:7. The resultant of development of this syndrome vary from fetal termination with compound malformations and rigorous growth deficiency to little sign and syndrome, including adults with no recognizable physical abnormality. ^(1,2,3)

Symptoms

Growth retardation

Growth retardation or undersized physique because of  skeletal system alteration. Uneven and asymmetric restriction of long bones, predominantly in the humerus (upper bone) and the femur (thigh bone). This happened due to toughened blemish of calcium on the heads or “growing portion” of the long bones and also found in the cartilage of the skeletal system.

The function of the cartilage is to provide cushioning between bones to prevent friction and play a role in connectivity, as they are connective tissue.  For growing child cartilage is an important site of the growth, as the initial stage growth of the skeletal system is beginning with cartilaginous portion and in future they gradually turned to bone.

Skeletal system

• The skeletal system alteration also affects the vertebra, chest bone, hip bone, feet and finger. Certain included characteristics locked in a bowed pose due to stiffness of the spine joints.  Extra finger growth, clubbed feet (twisted feet), malformed hip etc.

Craniofacial manifestation

• Typical craniofacial manifestation: This includes an abnormal enlarged forehead (frontal bossing), compressed zygomatic bone (cheek bones), a flattened overpass of the nose, inverted nostrils and deformed ears.
• Hearing problem or in extreme deafness due to deformed ears.

Dermal changes

Dermal changes or skin structure alteration: After birth, infants may have reddened and thickened skin. These are associated with scaling and dryness of the skin, followed with blotchy patches all over the body. Some children also have lighter or darker skin in contrast with surrounding area due to hypo or hyper-pigmentation. Over the period of time this may rectified in most of the cases. In scalp also this type of patches is developed and hair growth is ceased on that particular portion and sometimes scarring may also develop. Sometimes patchy area of the scalp has brittle and luster less hair growth. Nails are also easily cracked.

Eye

Malfunctioning in the eye: Congenital cataract or infancy cataract is quite common symptoms of the conradi hunermann syndrome. Onset of cataract causes blurred vision. Other eye related abnormalities include microphthalmos (small sized eye), microcornea (reduced corneal size), palpebral fissures or eyelid folds in downward slanting, nystagmus (involuntary rapid eyeball movement. Optic nerve degradation can cause significant reduction of eye sight. ^(1,4,6)

Causes

The conradi hunermann syndrome is a resultant of abnormal genetic mutation. The involved gene is emopamil-binding protein (EBP) gene. Sometimes this mutation arises arbitrarily without any specific reason. X-linked dominant trait is usually linked with this abnormal gene mutation, usually hereditary trait is responsible for autosomal incidence, as DNA fragments obtained from either father or mother is involved in this type of abnormal genetic disorder. EBP gene is taking part in the production of cholesterol and Vitamin D. ^(1,4,5)

Diagnosis

Diagnosis of the conradi hunermann syndrome is carried out by following tests:

The X-ray  can detect  calcium spotting or chondrodysplasia punctata at the head of the long bone and cartilages.

Hematological test

Assessment of blood plasma in gas chromatography-mass spectrometry and finding of high level of  sterols indicates the abnormal mutation of emopamil-binding protein (EBP) gene, as EBP gene mutation causes accumulation of sterols in plasma and certain types of tissues.

Genetic testing

Genetic test can be conducted for confirmation and can detect the trait of genetic mutation, which causes the conradi hunermann syndrome. ^(1,4)

Treatment

Multiple disorders are associated with conradi hunermann syndrome. The symptomatic variations are also varied with individual to individual. Therefore the treatment modalities applied to the management of the conradi hunermann syndrome need a group of specialists, who can discuss and decide the treatment plan for a particular patient. The same treatment approach cannot be applied to every patient and need to tailor therapy as per severity of the symptoms.

The usual medical team of the specialists for managing the CHD patients includes pediatricians, orthopedists, dermatologists, ophthalmologists and other healthcare providers.

Different assigned treatments

• Inconsistence length of the leg need orthopedic measures; for correction of extra finger or toe (polydactyly) surgical intervention usually taken; abnormal curveture of the spine (kyphoscoliosis) need periodic clinical assessment, as this can suddenly appear and rapidly progress at any age.
• Operation may also recommend for rectification of craniofacial malformations. The different surgical process and complications depend on the characteristic, severity, and permutation of structural irregularities, related indications, and supplementary features like age of the child, physical condition of the patients, etc.
• Any interference of the cataracts with the vision need to operative intervention for elimination of the cataract coating, in some cases artificial lenses need to incorporate, Further may require ophthalmological surgery for correction of the lenses, for achieving good vision.
• Application of emollients to increase the softness of the skin, application of oil in the body before bath in also recommended to protect the excess dryness, scaling and for maintaining the natural luster.
• Standard therapy for cardiac problem, the renal problem and auditory impairment must be taken, depending upon the patient need.
• Speech therapy, physical therapies and occupational therapies also need for some patient and they improve the patient condition.
• Genetic counseling may be beneficial for exaggerated patients and their family members.

All the treatment process may not be one time requirement, therefore it is advisable to take periodic surveillance measures for improved quality of life with extended periods of survival. ^(1,4)

Images

References

1. Conradi Hünermann Syndrome; National organization for rare diseases; Retrieve from: http://rarediseases.org/rare-diseases/conradi-hunermann-syndrome/
2. Cassandra L. Kniffin (2015); Chondrodysplasia Punctata 2, X-Linked Dominant; CDPX2;Retrieve from: http://www.omim.org/entry/302960
3. Conradi-Hunermann syndrome; Contact a Family; Retrieve from: http://www.cafamily.org.uk/medical-information/conditions/c/conradi-hunermann-syndrome/
4. Melissa A Dempsey, Christopher Tan, and Gail E Herman, (2011); Chondrodysplasia Punctata 2, X-Linked; Retrieve from: http://www.ncbi.nlm.nih.gov/books/NBK55062/
5. Cristina Has, Leena Bruckner-Tuderman, Dietmar Müller, Michaela Floeth, Elzo Folkers, Diana Donnai and Heiko Traupe; (2000); The Conradi–Hünermann–Happle syndrome (CDPX2) and emopamil binding protein: novel mutations, and somatic and gonadal mosaicism; Retrieve from:http://hmg.oxfordjournals.org/content/9/13/1951.full
6. Conradi Hünermann Syndrome (2015); WebMD Medical Reference from the National Organization for Rare Disorders; Retrieve from: http://www.webmd.com/children/conradi-hunermann-syndrome