The test measures pyrroles (cryptopyrrole - 2,4 dimethyl-3 ethylpyrrole) in the urine. In the body porphyrins are formed from pyrroles (cyclic molecules consisting of four pyrroles linked together). The most important porphyrin in the human body is haem. Haem is mainly formed in the liver for the synthesis of heme proteins (in particular cytochrome P450) and in the bone marrow in the formation of red blood cells.1
Usually only a small amount of pyrrol is excreted in the urine. Clinically elevated levels of pyrroles (pyroluria or "mauve factor") in the urine have been found in specific mental / mental disorders, including schizophrenia. Presumably, the elevated pyrrol excretion with the urine is caused by a (hereditary or acquired) defect in the haem synthesis(1).
Kryptopyrrole binds chemically with the active form of vitamin B6 - pyridoxal-5-phosphate - (not with pyridoxine!) And can then form complexes with zinc (2). Increased excretion of cryptopyrrol can therefore be a deficiency of the active form of vitamin B6 and in also cause zinc to a lesser extent.
Persons with an elevated pyrrol in the urine may have symptoms associated with shortages of the nutrients mentioned above. The condition is relatively common in certain families, which suggests a genetic predisposition.
According to Pfeiffer, 30 to 40% of people with schizophrenia have an elevated pyrrol in the urine. And according to him, these patients would be well treatable with (relatively high doses) of vitamin B6 and (nutritional doses) zinc (and possibly also manganese). These patients often have white dots on the nails, problems with remembering dreams, a sweet breath and pain in the upper left of the abdomen. Other possible complaints are anemia that does not react to iron (but also to vitamin B6), intolerance to barbiturates and hypersensitivity to (sun) light (2).