|Year : 2016 | Volume
| Issue : 4 | Page : 265-267
Hemraj Soni1, Rajkumar Goyal2, Aliza Mittal3, Preeti Agrawal4, Binit Sureka5
1 Consultant Pediatrician, Department of Pediatrics, SMS Medical College, Jaipur, India
2 Consultant Pediatrics, Department of Pediatrics, Apex Hospital, Jaipur, India
3 Department of Pediatrics, VMMC and Safdarjung Hospital, New Delhi, India
4 Consultant Radiologist, Getwell Polyclinic and Hospital, Jaipur, India
5 Department of Radiodiagnosis, VMMC and Safdarjung Hospital, New Delhi, India
|Date of Web Publication||16-Nov-2016|
Dr. Binit Sureka
Department of Radiodiagnosis, VMMC and Safdarjung Hospital, New Delhi - 110 029
Source of Support: None, Conflict of Interest: None
Genitopatellar syndrome is an extremely rare, autosomal dominant disorder characterized by the association of absent patellae, genital anomalies, dysmorphic features (coarse face, large nose, microcephaly), renal anomalies (multicystic kidneys or hydronephrosis), cardiac defects, and intellectual deficit. Constant skeletal manifestations include flexion deformities of the knees and hips with club feet. It is caused by mutations in KAT6B which encodes for histone acetyltransferase 6B enzyme involved in gene regulation.
Keywords: Genital anomalies, mental retardation, patella
|How to cite this article:|
Soni H, Goyal R, Mittal A, Agrawal P, Sureka B. Genitopatellar syndrome. J Clin Neonatol 2016;5:265-7
| Introduction|| |
Genitopatellar syndrome (GPS) is a rare disorder with characteristic craniofacial features, congenital flexion contractures of the lower limbs, absent or abnormal patellae, urogenital anomalies, and severe psychomotor retardation. Here, we report a newborn with all typical features of GPS. GPS is estimated to occur in <1/million people. The first case was reported by Goldblatt et al. Only 18 cases have been reported in the medical literature so far.
| Case Report|| |
A newborn male child was born to 2nd gravida, nonconsanguineous parents. Both parents were physically and intellectually normal. There were no known teratogenic exposures. On the first gravida, it was intrauterine death of twin male fetuses at 28 weeks of gestation. Neither autopsy nor other investigations were done.
The baby was delivered at 41 weeks with a weight of 2.8 kg (3rd centile), length 49 cm (10–25th centile), and a head circumference of 32 cm (3rd centile). Initially, his respiratory efforts were poor and he had apneic and bradycardic episodes. He immediately cried after birth with Apgar score of 8/10 and 9/10 at 1 and 5 min, respectively. Antenatal ultrasonography was reported normal, with no other significant history.
On initial physical examination, he has coarse facies with depressed nasal bridge, bulbous nose, prominent cheeks, and microretrognatia. The ears were normal, except dimple on earlobe. The palate was high arched. There were single palmer creases and camptodactyly with contracture of proximal interphalangeal joints in the 3rd and 4th fingers. He also had overlapping of the 2nd, 3rd, and 4th fingers, ulnar drift, and clinodactyly of both hands. Clinical examination and radiographs of the pelvis showed bilateral hip dislocation and flexion contractures of knee joints and absence of patella [Figure 1] and [Figure 2]. He had club foot on the left and calcaneovalgus deformity on the right foot with congenital ulnar drift of toes. He also had short, webbed neck with wide-spaced nipple (internipple distance was 10 cm). Sacral dimple was present. He had scrotal hypoplasia with no palpable testis bilaterally and small penis, which gave an initial look of ambiguous genitals.
|Figure 1: (a) Clinical photograph showing genital abnormality and (b) club foot|
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|Figure 2: (a) Pelvic radiograph showing bilateral hip dislocation with hypoplasia of ischia and inferior pubic rami, absence of patella and flexion deformity at hip and knee, and club foot (b) wrist radiograph showing brachydactyly|
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Various radiological investigations were also done. Magnetic resonance imaging of the brain showed evidence of agenesis of the corpus callosum and colpocephaly [Figure 3]. Echocardiography showed atrial septal defect (ASD) and patent ductus arteriosus (PDA). Skeletal survey showed dislocated bilateral femoral head, hypoplastic inferior pubic rami, spina bifida of L4, L5, and sacral vertebra. Computed tomography showed bilateral absent patella, multiple small bilateral renal cysts, relatively small left kidney, bilateral hydronephrosis (R > L), and pelvic abscesses. G-banded chromosomes at the 400 band level of resolution, prepared from a blood sample, showed a normal male karyotype. After birth, initially he accepted feeds well and passed motion and urine in usual way, but later the child succumbs to death due to sepsis.
|Figure 3: Sagittal T2-weighted magnetic resonance image showing corpus callosum agenesis|
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| Discussion|| |
GPS is a rare disorder consisting of abnormal or missing patella, microcephaly, severe psychomotor retardation, and characteristic coarse facial features including broad nose and small or retracted chin associated with congenital flexion contractures of the lower extremities and urogenital anomalies.,,, It has an autosomal dominant inheritance where the mutation in the KAT6B is responsible for the anomaly.
The genital abnormalities in affected male typically include cryptorchidism and underdevelopment of the scrotum. Affected females can have clitoromegaly and small labia.,, Missing or underdeveloped patella is the most common skeletal abnormality associated with GPS. Affected individuals may have additional skeletal problems including joint deformities (contractures) involving the hips and knees, spina bifida, ischial hypoplasia, radioulnar synostosis, and clubfoot.,,
GPS is also associated with delayed development and intellectual disability, which are often severe. Affected individuals may have microcephaly, structural brain abnormalities including heterotopia and agenesis of the corpus callosum., The patients may also have distinctive facial features such as prominent cheeks and eyes, a nose with a rounded tip or a broad high nasal bridge, cleft palate, micrognathia, prognathism, and narrowing of the head at the temples. Many affected infants have hypotonia that leads to breathing and feeding difficulties. Renal anomalies are also consistently observed including multicystic kidneys and hydroureteronephrosis., Congenital heart defects include ventricular septal defect, ASD, PDA, patent foramen ovale, and abnormal aortic arch.,, The condition can also be associated with abnormalities of lungs, anal canal, thyroid, and teeth. The major and minor features of GPS are illustrated in [Table 1].
In 1988, Goldblatt et al. first reported a 4-year-old boy with hypoplastic patellae, mental retardation, scrotal hypoplasia, skeletal deformities, renal anomalies, flattened nasal bridge, and short stature. Later, in 2000, Cormier-Daire et al. reported seven patients with genital anomalies, facial dysmorphism, renal anomalies, absent patella, and severe mental retardation. The condition is now known as GPS. Cytogenetic analysis was normal in all cases. The absence of the patella is listed by Cormier-Daire et al. as a pathognomonic feature of the GPS and the same is emphasized in the syndrome name. Absent patella can occur as a part of various dysplasias, but these conditions do not exhibit characteristic extraskeletal manifestations as seen in GPS.
There is a 25% recurrence risk in patient's sibling. Recurrence risk in patient's offspring will not increase unless spouse is a carrier. The syndrome is a crippling disorder that not only affects one physically but also causes mental handicaps. There is no definitive treatment. Only supportive and symptomatic treatment is available in the form of educational intervention, speech therapy, physiotherapy, and surgical release of contractures.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2], [Figure 3]