A case of bilateral corneal opacity
George Emmanuel Comia, MD, Ruben Lim Bon Siong, MD
ACROMESOMELIC dysplasia is an extremely rare, progressive, autosomal recessive disorder characterized by premature fusion of the metaphyseal area of certain long bones. This condition is diagnosed on the basis of skeletal and radiologic changes occasionally present at birth, but which become more marked in the first two years of life. A study by Ianakiev et al, localized six consecutive markers on chromosome 9 after gene mapping studies on four affected individuals. Patients with this condition exhibit unusually short forearms and lower legs and short stature during the first years of life. There may also be some lag in gross-motor performance, but intelligence is normal. Abnormalities include bowed radius, brachydactyly, carpal synostosis, cone-shaped epiphyses of phalanges, irregular end-plates to vertebrae, macrocephaly, mesomelia of legs or hindlimbs, mesomelia of arms or limbs, barrel chest with pectus carinatum, platyspondyly, restriction of supination or pronation, short phalanges, wide metaphysis, and wide phalanges. Other occasional abnormalities are relatively large big toe and corneal clouding. We report the case of a 6-year-old female born full term via primary low-segment caesarean section for breech presentation to a 28-year-old G2P1 (1-0-0-1) with no fetomaternal complications. At 2 years, she had stunted growth, a prominent chest wall, and gross deformities of limbs, but no developmental delay. Consultation at a local hospital was made with no definitive management. At 4 years, the patient was brought to the University of the Philippines–Philippine General Hospital (UP–PGH) pediatrics outpatient department where she was assessed to have rickets. Ancillary procedures showed delayed bone maturity and levoscoliosis. Differential diagnoses included a primary skeletal problem such as osteochondrodysplasia, probably acromesomelic dysplasia. On physical examination, the patient showed stunted growth and short neck; pectus carinatum; enlarged medial and lateral malleoli of lateral, radial, and medial heads of both wrists; bowed radius; short forelimbs and hindlimbs; short and stubby fingers and toes; and genu valgum. Neurologic examination was normal.
Ophthalmologic examination revealed best-corrected visual acuity of 6/12 for both eyes. Pupils were 3 mm and reactive to light. Corneal diameters were 12 mm for both eyes with normal corneal thickness, intact epithelium, and diffuse mid to posterior stromal haze. The anterior chambers were formed with normal iris, round pupil, and clear lens. Intraocular pressure, gonioscopy, and findings on indirect ophthalmoscopy were unremarkable. Corneal topography showed symmetrical bow-tie astigmatism of –3.38D for the right eye and –3.00D for the left eye. Pachymetry was normal. Specular microscopy was unreliable because of poor visibility.
Cloudy cornea is an occasional finding in patients with acromesomelic dysplasia, and the relationship between the two has not been delineated. In a case by Clarke et al., the cornea obtained after lamellar keratoplasty showed replacement of most of the Bowman’s membrane and the stroma by fibrous tissue, with accumulation of extracellular acid mucopolysaccharides. They concluded that since the opacities were present at birth, the pathologic process may have occurred in utero and may have included inflammation, trauma, or toxic effects. The biochemical defect in this disease is not known, but may be responsible for the scarring and the accumulation of mucopolysaccharide material proximal to a possible local enzyme block. The treatment of acromesomelic dysplasia is directed toward the specific symptom and physical characteristics seen in each patient. Treatment may require the coordinated efforts of a team of specialists such as pediatricians, orthopedists, physical therapists, and ophthalmologists. Ophthalmic treatment includes corrective lenses for errors of refraction and polarized lenses for symptoms of glare. The patient still has good visual acuity and keratoplasty is, therefore, not indicated yet. Follow-up is necessary to assess the progression of the disease and to decide on appropriate management of symptoms.
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