We describe an improved cytochemical procedure for detecting the presence of cytoplasmic lipid droplets (Jordans’ bodies) in blood cells from patients suffering from neutral lipid storage diseases (NLSDs). The method employs Oil red O (ORO), Nile red (NR) or, preferably, Bodipy (4,4-difluoro-1,3,5,7,8-pentamethyl-4-bora-3a,4a-diaza-s-indacene) staining, coupled with DAPI (2-(4-amidinophenyl)-6-indolecarbamidine) staining of nuclei, to visualise clearly by fluorescence microscopy the presence of abundant neutral lipids (triacylglycerols and cholesterol esters) in granulocytes and monocytes. Using these reagents, we easily identified Jordans’ bodies in buffy coats from patients affected by Chanarin–Dorfman syndrome (NLSD with ichthyosis) and NLSD with progressive myopathy, a laboratory finding critical for the diagnosis of both inherited metabolic disorders. Due to their yellow-gold and green fluorescence arising selectively from neutral lipid binding and their water solubility that makes alcohol unnecessary for staining, NR and particularly Bodipy are superior to ORO for the specific detection of Jordans’ bodies in leucocytes.

Neutral lipid storage diseases (NLSDs) are a clinically heterogeneous group of non-lysosomal inherited disorders characterized by a cytoplasmic accumulation of lipid droplets (LDs) in most tissues. Rather than being an inert lipid inclusion, an impression given prima facie by their simple morphological structure under the light microscope, LDs were recently shown to be distinct organelles consisting of a core of neutral lipids, predominantly triacylglycerols or cholesteryl esters, that are surrounded by a monolayer of phospholipids and associated proteins.^1,2 LDs take active part in lipid metabolism as well as in membrane trafficking and other cell fuctions.³

Since the pioneering observation by Jordans of numerous LDs in the leucocytes of two Dutch brothers suffering from progressive muscular dystrophy,⁴ several reports have described the presence of abundant triacylglycerol deposits in the non-adipose cells of patients manifesting a variety of defects. Clinical phenotypes include myopathy (skeletal and heart muscle), liver damage, ataxia, neurosensory …