GRP-78 is a glucose-regulated protein belonging to the HSP-70 family, which is mainly present in the endoplasmic reticulum where it mediates several cellular processes as a chaperon, including protein folding, degradation of misfolded proteins, regulation of calcium homeostatis and sensing the endoplasmic reticulum stress.[32, 37-41] Recent studies indicate that a fraction of GRP-78 is also translocated to the cell surface in many cell types,[41] wherein it acts as the receptor mediating penetration and damage of endothelial cells by Mucorales, leading to the observed angioinvasion.[32] Mice with diabetic ketoacidosis
have an increased expression of GRP-78 in sinus, lungs JQ1 concentration and brain, and anti-GRP-78 serum can protect such mice from mucormycosis, indicating a plausible role of GRP-78 overexpression in susceptibility of diabetics
to this disease.[32, 39] It is generally believed that distinct clinical presentations of mucormycosis are associated with specific underlying risk factors, with ROC, pulmonary, gastrointestinal and cutaneous types occur in patients with diabetes, haematological malignancies or neutropaenia, severe malnutrition, and trauma or burns respectively.[1, 4-7] However, uncontrolled diabetes has been found as the major factor in all types of mucormycosis in India except the isolated renal form, although ROC manifestation remains the most common clinical type and is significantly associated with uncontrolled diabetes.[1, 4-7, HSP90 20, 21] As the Alpelisib majority of Indian patients have diabetes and metabolic acidosis as the major risk factors, the principal management modalities in such cases include a control of hyperglycaemia and prompt reversal of ketoacidosis, along with surgical debridement and amphotericin B therapy.[3] It is hypothesised that a decrease in diabetes-associated mucormycosis in USA in recent years may be attributed to an increased use of statins
in diabetic patients and the inhibitory action of statins against mucoralean agents.[42] Although statins are regularly prescribed in Indian patients with diabetes, no fall in the number of diabetes-associated mucormycosis cases has been reported from this country.[3] Therefore, a detailed study is required for assessing the role of statins against mucormycosis. Among the different clinical types of mucormycosis, cutaneous and rhino-cerebral types have a better survival rate due to possibility of an early diagnosis. Though majority of the Indian patients have rhino-cerebral presentation, the mortality rate of mucormycosis remains high (nearly 50%) in India.[4] This is largely due to a delay in seeking medical attention, diagnosis and therapy.[3] Apart from the common clinical types, isolated renal mucormycosis in apparently healthy hosts is being reported as a new clinical entity in India.[4-6, 43] Although the kidney is involved in nearly 22% cases of disseminated mucormycosis,[44] isolated renal mucormycosis is described rarely in literature.