Chorea-acanthocytosis (ChAc, also called choreoacanthocytosis) is a rare hereditary disease caused by a mutation in a gene that directs structural proteins in red blood cells. It belongs to a group of four diseases characterized under the name neuroacanthocytosis. When a patients blood is viewed under a microscope, some of the red blood cells appear thorny. These thorny cells are called acanthocytes. Other effects of the disease may include epilepsy, behaviour changes, muscle degeneration, and neuronal degradation similar to Huntingtons disease. The average age of onset of symptoms is 35 years. The disease is incurable and inevitably leads to premature death. Chorea-acanthocytosis is a very complex autosomal recessive adult-onset neurodegenerative disorder. It often shows itself as a mixed movement disorder, in which chorea, tics, dystonia and even parkinsonism may appear as a symptom.This disease is also characterized by the presence of a few different movement disorders including chorea, dystonia etc.Chorea-acanthocytosis is considered an autosomal recessive disorder, although a few cases with autosomal dominant inheritance have been noted. Signs and symptoms
There are multiple symptoms that can help this disease to be diagnosed, this disease is marked by the presence of acanthocytes in blood (these acanthocytes can sometimes be absent or even make a late appearance in the course of the disease.)
The sensitivity is higher in patients with interstitial nephritis induced by methicillin or when the Hansels stain is used. However, a 2013 study showed that the sensitivity and specificity of urine eosinophil testing are 35.6% and 68% respectively. Isosthenuria
Blood in the urine and occasional RBC casts
Sterile pyuria: white blood cells and no bacteria. About 50% of patients with AIN have pyuria. Nephrotic-range amount of protein in the urine may be seen with NSAID-associated AIN. Low grade proteinuria may be seen in a majority of other causes of AIN. White blood cell (WBC) casts: Fewer than one in five patients with AIN have WBC casts in urine. Pathology
While non-invasive patient evaluation (physical examination, blood and urine testing, imaging studies) can be suggestive, the only way to definitively diagnosis interstitial nephritis is with a tissue diagnosis obtained by kidney biopsy. Pathologic examination will reveal the presence of interstitial edema and inflammatory infiltration with various white blood cells, including neutrophils, eosinophils, and lymphocytes. Generally, blood vessels and glomeruli are not affected. Electron microscopy shows mitochondrial damage in the tubular epithelial cells, vacuoles in the cytoplasm, and enlarged endoplasmic reticulum. Gallium scan
The sensitivity of an abnormal gallium scan has been reported to range from 60% to 100%. A study of Gallium scan in 76 patients [23 with AIN, 8 with biopsy-proven AIN] showed an AUC of 0.75.