<prompt> Blue sclera is characteristic of?Amelogenesis ImperfectaOsteogenesis imperfectTetracycline hypoplasiaFluorosis  <response>: ANSWER: B Osteogenesis imperfectaREF: Khurana 4th ed page 131, Yanoff 2nd ed page 518BLUE SCLERA:It is an asymptomatic condition characterised by marked, generalised blue discolouration of sclera due to thinning. It is a typical association of osteogenesis imperfecta. Osteogenesis imperfecta is an inherited condition that involves the skeleton, ear, joints, teeth, skin, and eyes. Van der Hoeve in 1918 described the three main signs of osteogenesis imperfecta: blue sclera, deafness, and bone fractures. The characteristic blue sclera is caused by thinness and transparency of the collagen fibers of the sclera that allow visualization of the underlying uvea.Note:Blue sclera is considered normal in premature infants and in white newborns, is pathologic if persists beyond 1st month of infancy.Causes of blue sclera:Osteogenesis imperfecta Characteristic but not seen in Type IVIron deficiency anemia 87Pseudohypoparathyroidism 15Homocystinuria 5Marfans syndrome 3Ehlers-Danlos syndrome Type VI occasionallyMinocycline therapyTurner syndrome very rareOcular staphyloma very rareIncontinentia Pigmenti very rarePseudoxanthoma elasticum very rareHypophosphatasia very rareCrouzon s disease very rare 