ABSTRACT
A preterm infant who underwent bilateral laser photocoagulation for the treatment of stage 3 retinopathy of prematurity (ROP) is presented because she was incidentally diagnosed with grade 3 lipemia retinalis by dilated fundoscopy at post-laser 2 weeks. Meticulous ophthalmologic examination is imperative in premature newborns for not only ROP screening but also detecting any concomitant ocular abnormalities, which can be sight-threatening or even life-threatening.
Introduction
Lipemia retinalis (LR) is an unusual and rare pathology characterized by whitening of the retinal vessels due to high plasma triglyceride levels and scattering of light by triglyceride-laden chylomicrons. Early findings are generally observed in the peripheral retina; however, pathognomonic symptoms tend to appear at the posterior pole when plasma triglyceride levels exceed 2,500 mg/mL.1,2,3 The disease can be graded as early, moderate, or marked according to retinal appearance.4 As long as LR is not associated with complications like retinal vein occlusion, it generally does not interfere with visual acuity.4 However, various electroretinographic changes may be noted in cases with LR.5
Discussion
Careful fundoscopic screening of premature infants is mandatory to identify the signs of ROP. Moreover, various ocular and retinal pathologies can be diagnosed incidentally during dilated routine examinations.6 Several metabolic disorders can also be detected in newborns during a thorough ophthalmic examination, even in very early stages before any prominent symptoms and signs become evident. In 1880, Heyl first described LR, which is characterized by milky-creamy white colored retinal vessels. This typical appearance generally occurs when serum triglyceride level is higher than 2500 mg/dL. Isolated hyperlipidemia without accompanying hypertriglyceridemia does not present with LR.1,2,3,4,5,6,7 Hypertriglyceridemia may also occur in familial disorders like apolipoprotein C-II deficiency, LPL deficiency, and endogenous circulating low-density lipoprotein inhibitor.1 Yin et al.8 reported a homozygous p.G215E mutation in the LPL gene in a 6-week-old full-term baby with hypertriglyceridemia and LR.
Babies born preterm and those with intrauterine growth restriction may be more prone to LR due to major risk factors for hypertriglyceridemia such as low LPL activity, parenteral nutrition, and consumption of medium chain triglyceride formulas, which are very common supplements for low-birth-weight infants.6,7,8 Persistence of uncontrolled high serum levels of cholesterol and triglycerides may lead to possibly fatal morbidities including premature atherosclerosis and coronary artery disease, pancreatitis, and hepatic failure, especially in preterm and term newborns and infants.6,7,8,9,10 Hence, early diagnosis of LR in such cases is crucial. Although it is known that LR generally does not affect visual acuity in sufferers, Dinc et al.11 reported a pregnant Turkish women with no family history of hyperlipidemia who developed bilateral severe visual deterioration and whose visual acuity improved after delivery and increased to 20/20 with a normal fundoscopic appearance in both eyes after low-fat diet, physical exercise, and drug treatment with 3-hydroxy-3-methyl-glutaryl-coenzyme A inhibitor.
In the present case, retinal findings totally regressed in accordance with the rapid decrease in serum triglyceride and cholesterol levels after the commencement of a strict low-fat diet. Systemic assessment and pertinent laboratory tests should be carried out in patients with LR in order to determine the underlying cause, which may seriously affect the end organs due to high serum lipid levels. Therefore, early diagnosis can even be life-saving. Moreover, examination of the parents and siblings, genetic counseling, and dietary recommendations are among the essential steps to be taken.
