Cartilage hair hypoplasia is a rare multisystemic genetic disorder demarcated by a short stature from birth, hypoplastic hair, various skeletal abnormalities and a variable degree of immunodeficiency that can be fatal in the absence of an early diagnosis. Clinical signs, results from imaging studies, and genetic testing are necessary parts of the diagnostic workup.
Signs and symptoms of cartilage hair hypoplasia (CHH) may be evident from birth, when disproportionately short limbs, considered as a cardinal feature of CHH, are identified  . Consequently, a short stature is evident in all patients, with metaphyseal dysplasia being the principal pathological event  . Bowing of the lower extremities, a prominent reduction in the length of the tibia compared to the fibula, very short hands characterized by increased laxity of the metacarpal, interphalangeal and phalangeal joints, and incomplete extension of the elbow joint are important additional skeletal manifestations of CHH  . Apart from growth abnormalities, the appearance of a fine, light-colored and sparse, short hair is the second main component of the clinical presentation . Hypopigmentation of the skin and nail dysplasia can be identified in some cases . Immunodysfunction, humoral and/or cell-mediated, is readily observed, ranging from mild subclinical forms to severe combined immunodeficiency (SCID)  . In fact, neutropenia and lymphopenia frequently create favorable conditions for recurrent infections, seen in up to 60% of patients, and are the principal causes of death in CHH . Gastrointestinal conditions, such as malabsorption, celiac disease or Hirschsprung's disease are identified in about 18% of cases, which may be one of the contributing factors for failure of infants to thrive throughout childhood, another possible symptom . Finally, immunodeficiency combined with anemia that is commonly noted shows a significant predilection toward hematologic malignancies, especially lymphomas  .
Entire Body System
Anemia is seen in over 80% of patients with cartilage-hair hypoplasia (CHH). While this is usually mild and self-limited, some patients demonstrate a severe, persistent anemia resembling that seen in Diamond-Blackfan anemia (DBA). [ncbi.nlm.nih.gov]
Finally, immunodeficiency combined with anemia that is commonly noted shows a significant predilection toward hematologic malignancies, especially lymphomas. [symptoma.com]
CONCLUSIONS: This study confirms an increased risk of cancer, especially non-Hodgkin's lymphoma, probably attributable to defective immunity, among patients with CHH. [ncbi.nlm.nih.gov]
Thus the SMR for non-Hodgkin's lymphoma alone would be approximately 80. In addition, there were two accidental deaths (ages 42 and 24 years; SMR 3.8, 95% CI 0.5 to 14). [adc.bmj.com]
The most common cancers are non-Hodgkin lymphoma, squamous cell carcinoma, leukemia, and Hodgkin lymphoma. The reason why individuals with McKusick type metaphyseal chondrodysplasia have increased risks for cancer is unclear at this time. [rarediseases.org]
In fact, neutropenia and lymphopenia frequently create favorable conditions for recurrent infections, seen in up to 60% of patients, and are the principal causes of death in CHH. [symptoma.com]
It is characterized by disproportionate short stature, fine sparse hair, ligamentous laxity, hematological abnormalities with anemia, a predisposition to malignant tumors, and recurrent infections usually due to cellular and/or humoral immunodeficiency [ncbi.nlm.nih.gov]
Treatment : Caution regarding weight gain Treat limb alignment and perform early joint replacement Shelf acetabular augmentation in some patients - to improve coverage of the misshapen femoral head Osteotomies may be helpful in realigning [slideshare.net]
Failure to Thrive
We report on a Thai girl who first presented with chronic diarrhea, recurrent pneumonia, and severe failure to thrive, without apparently disproportionate dwarfism. [ncbi.nlm.nih.gov]
- Gastrointestinal dysfunction: This can present with signs of malabsorption, diarrhea, celiac disease, and failure to thrive. This requires symptomatic treatment. [atlasgeneticsoncology.org]
Intestinal malabsorption presents as diarrhea, and decreased ability to gain weight (failure to thrive) in the newborn period. Most of the intestinal symptoms appear within the first two years of life. [rarediseases.org]
OS is usually accompanied by enlarged lymphoid tissues, protracted diarrhea, failure to thrive, and eosinophilia, which refers to the condition characterized by the presence of high amounts of eosinophils in either the blood or body tissues 21. [doi.org]
Cartilage-hair hypoplasia (CHH) is a rare autosomal-recessive disorder characterized by short-limbed dwarfism, sparse hair, and immune deficiency. [ncbi.nlm.nih.gov]
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. [ncbi.nlm.nih.gov]
Pre-existing autoimmunity and inflammatory skin lesions were a prominent feature in 5 of 16 patients (patient nos. 3, 5, 8, 11, and 12; Table 1 ). Thirteen patients were transplanted in early childhood (mean age 2.5 years). [bloodjournal.org]
This study suggests that Hirschsprung disease is associated especially with severe cartilage-hair hypoplasia: the patients with Hirschsprung disease had severe growth failure and a higher incidence of alopecia, infections, malignancies, and childhood [ncbi.nlm.nih.gov]
About 15% of affected individuals have complete hair loss (alopecia), which includes the scalp, eyelashes, eyebrows, and body hair. Decreased red blood cell production (anemia) has been reported in about 80% of affected individuals. [rarediseases.org]
Increased ligamentous laxity was present in 95%, limited extension of the elbows in 92%, increased lumbar lordosis in 85%, thoracal deformity in 68%, genu varum in 63% and scoliosis in 21% of the patients. [ncbi.nlm.nih.gov]
[…] peptide (PTHRP) receptor mental retardation short limbed dwarfism wide eyes monkey like stance ostebulbous metaphyseal expansion of long bones seen on xray Schmid's autosomal dominant defect in Type X collagen short limbed dwarfism excessive lumbar lordosis [orthobullets.com]
Other symptoms include short hands and possibly short, deformed limbs (varus). X-ray reveals metaphyseal lesions, especially in the knees, and large, round epiphyses during childhood. [orpha.net]
Bowing of the lower extremities, a prominent reduction in the length of the tibia compared to the fibula, very short hands characterized by increased laxity of the metacarpal, interphalangeal and phalangeal joints, and incomplete extension of the elbow [symptoma.com]
We have previously mapped the gene for CHH to the short arm of chromosome 9 in Finnish and Amish families. The CHH locus resides close to D9S163 within an interval of 1.5 cM flanked by D9S165 and D9S50. [ncbi.nlm.nih.gov]
The locus of the gene has been mapped to the short arm of chromosome 9. Patients with CHH usually suffer from cellular immunodeficiency. [en.wikipedia.org]
Signs & Symptoms Unevenly short arms and legs (short limbed dwarfism) are the most common features in McKusick type metaphyseal chondrodysplasia and are seen in around 100% of affected individuals. [rarediseases.org]
Mapping of the shortest region of overlap of deletions of the short arm of chromosome 9 associated with human neoplasia. Genomics 14, 437–443 (1992). 21 Anderson, M.A. & Gusella, J.F. [doi.org]
And a little girl who would grow up to be four feet tall with exceedingly short arms and legs does not fit that paradigm. Seventeen years later, we are on the verge of being able to do something when our image of perfection is threatened. [theguardian.com]
Before birth Possibly via prenatal ultrasound due to short extremities Genetic sampling if expected After birth X-ray findings Observation of common physical characteristics Confirmation by DNA testing of the RMRP gene via a blood test What are the common [littlepeopleuk.org]
[…] small chest with short ribs Plain radiograph short, bowed femurs with metaphyseal flare and irregularity eleven ribs, moderately short Flared and irregular metaphyses of multiple long bones are also associated with these dysplasias, as well as mild platyspondyly [radiopaedia.org]
Generalised severe platyspondyly Increased intervertebral disc height Open staircase vertebrae Kyphosis/ scoliosis Widening sclerosis irregularity of tubular bones Irregular femoral epiphysis Retarded bone maturation 17. [slideshare.net]
CHH must be considered in the differential diagnosis of a short stature that appears from birth and accompanying features such as hair hypoplasia and immunodeficiency that predisposes individuals to recurrent infections. For this reason, a meticulously performed physical examination is a pivotal step. Despite the genetic nature of the disorder, its mode of inheritance (autosomal recessive) does not mandate a positive family history, but nevertheless, the appearance of similar signs and symptoms in close relatives or siblings must be noted. Laboratory studies will reveal transient macrocytic anemia, lymphopenia with a decreased CD4+/CD8+ T-cell count, and neutropenia  . Imaging studies are used to distinguish CHH from numerous other causes of short stature. Metaphyseal dysplasia seen on X-rays of the limbs is the principal radiologic feature, accompanied by thickening and shortening of the tubular bones (distal femur, proximal tibia and bones of the hands), excessive length of the distal fibula, flaring of the costochondral junction, delayed ossification, and cone-shaped phalangeal epiphyses  . If these features are identified during infancy, CHH is a highly likely diagnosis, in which case genetic studies should be pursued to confirm the underlying cause. Sequencing of the mitochondrial RNA-processing (RMRP) gene, the main culprit in the pathogenesis of CHH, located on chromosome 9p13.3  , is available and advised whenever valid clinical suspicion exists based on clinical and radiographic criteria.
CD8 lymphocytopenia was identified as a novel phenotype associated with RMRP mutations. Significant, even intrafamilial, phenotypic heterogeneity was observed. [ncbi.nlm.nih.gov]
This could explain at least in part the severe lymphocytopenia in some patients with CHH and the observed low lymphocyte proliferation to specific mitogens in vitro. [bloodjournal.org]
- Horn J, Schlesier M, Warnatz K, et al. Fatal adult-onset antibody deficiency syndrome in a patient with cartilage hair hypoplasia. Hum Immunol. 2010;71(9):916-919.
- Riley P, Weiner DS, Leighley B, et al. Cartilage hair hypoplasia: characteristics and orthopaedic manifestations. J Child Orthop. 2015;9(2):145-152.
- Baradaran-Heravi A, Thiel C, Rauch A, Zenker M, Boerkoel CF, Kaitila I. Clinical and Genetic Distinction of Schimke Immuno-Osseous Dysplasia and Cartilage-Hair Hypoplasia. American journal of medical genetics Part A. 2008;146A(15):2013-2017.
- Shiasi Arani K. Cartilage Hair Hypoplasia: First report from Iran. Med J Islam Repub Iran. 2013;27(3):157-160.