#6086 NEUTRAL LIPID STORAGE DISEASE WITH RENAL INVOLVEMENT: A CASE REPORT

Abstract

Abstract Background and Aims Neutral lipid storage diseases (NLSD) are rare conditions caused by an inborn error of neutral lipid metabolism that results in a deficit in the degradation of cytoplasmic triglycerides and a consequent abnormal storage of the neutral lipids. Their accumulation in cytoplasmic lipid droplets in most tissues of the body results in a very heterogeneous phenotype: myopathic syndrome, intellectual deficit, cataract, neuropathy, cardiomyopathy, hepatomegaly are the main clinical manifestations. Less frequent conditions are diabetes, chronic pancreatitis and renal involvement. Method A 27-year-old woman visited our hospital on November 2022 because of progressive onset of edema, dyspnea, nausea and loss of appetite. The medical history showed that 4 years before she was diagnosed with diabetes mellitus and she has been suffering from severe muscle weakness (she was helping herself with the wheelchair) for two years. In 2017 a proctological evaluation showed an anal hypotonia from likely neuropathy. Blood chemistry tests revealed a metabolic acidosis, a decreased renal function, anaemia and nephrotic range proteinuria at the urinalysis. A bilateral pleural effusion was described at the chest radiograph and a circumferential pericardial effusion at a first echocardiogram. The ultrasound of the abdomen described a small size of the right kidney (90 mm) and an angiomyolipoma on the left kidney. Neurological examination showed a mild intellectual disability, facies with dysmorphic appearance and hypotonia of proximal and distal muscular masses of the upper limbs. Lower limbs showed a more pronounced strength deficit on the left and a hypotonia to proximal muscle masses. Electromyography showed a condition of severe sensitivity polyneuropathy: signs of chronic denervation and morphological alterations of the motor unit especially in the proximal districts of the lower limbs. Ophthalmological examination showed an advanced cataract. Cardiological evaluation through heart echo scanshowed a dilated heart disease with ventricular function and dilation of the pulmonary artery. A quadriceps muscle biopsy finally revealed myogenic features consistent with neutral lipid storage disease. Fabry test came back negative. Despite several drug treatments, the patient continued to be asthenic, inappetent and the oxygen therapy could not be removed because frequent episodes of desaturation. The deterioration of the patient's clinical conditions required the onset of dialysis immediately. Unfortunately, despite adequate information on the risks of possible refusal, the patient denied consent for central venous catheter placement and hence the beginning of renal replacement therapy. Sadly, the patient was lost to follow up and it was not possible to carry out other diagnostic investigations. Results Our patient developed an end-stage renal disease in the framework of a neutral lipid storage disease. Since cytoplasmic lipid droplets are ubiquitous organelles, we can assume that in this case, kidney involvement is due to a pathogenetic mechanism similar to that of other storage diseases such as Fabry disease (Table 1). Conclusion Here we describe a 27-year-old NLSD female patient showing late onset myopathy and difficulties in mobilization in association with severe cardiac and ocular involvement, mild intellectual disability, diabetes mellitus type 2 and end stage renal disease. Our data expand the clinical manifestations of NLSD, providing further evidence for clinical NLSD heterogeneity and mainly, further evidence for storage diseases with renal involvement.