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Information about HPU testing

The HPU-Test® is a screening test like the PKU-Test, which is better known as the heel prick test to determine which babies may later develop the disease Phenylketonuria (PHU). However the HPU-Test® is not carried out using blood, but urine. Similarly, the HPU-Test® can also determine which individuals may later develop symptoms of HPU.

HPU does not develop into a specific disease, but rather leads to a range of symptoms, from mild to very severe, such as joint complaints (hypermobility), menstrual complaints, reduced fertility, pelvic instability, depression, cardiovascular disease, anemia, diabetes, thyroid problems and excess weight gain during pregnancy. HPU is found mainly in women.

If you recognize yourself, even partially, in the pattern of symptoms that can be caused by HPU, you may ask yourself “Do I have HPU?” If you recognize the symptoms that can arise from direct vitamin B6, zinc and manganese deficiencies, it may be useful to find an answer to your question by further investigation.

In particular, increased joint mobility (hypermobility) is typical in people with HPU. Many women can extend their little finger backwards, or toch their lower arm with their thumb (see photo1 and photo 2). Hypermobility of the temporomandibular joint is also common. In addition, many women with HPU experience fatigue. Fatigue in HPU may be due to hypoglycaemia, reduced liver function, low histamine levels and/or adrenal function. As a result, countless women with fatigue issues consult medical and alternative health practitioners in search of a cure and are often incorrectly diagnosed or treated. An example is the ‘umbrella diagnosis’ chronic fatigue syndrome (CFS or ME). Some women given this diagnosis actually have HPU and can, therefore be treated accordingly.

If you would like to find out whether you have HPU, you can fill out the questionnaire that you find on this site. The questionnaire is also included in the book Do you have HPU?

HPU test options

HPU investigations consists of a number of test options. In addition to the HPU questionnaire on this website, the simplest option is to test the urine for the presence of the hemopyrrollactam complex. This is a simple urine test for which a small amount of mid-flow morning urine is required. The test costs € 57,23. Individuals who are chronically ill or bedridden should consider an HPU test based on a 24-hour urine. The costs are € 69,10.

HPU screening

The HPU screening consists of multiple tests that are carried out using a blood sample. HPU screening consists of a fructosamine assay, an IgA total gluten test, a whole blood histamine assay, DAO and a simple hormone test. The costs of this blood test are € 164, -.

False positive results

Hemopyrrolactam complex (HPL) is excreted in the urine in most porphyria diseases, therefore it is possible that another porphyria disease may be present. The concentration of HPL can be influenced by chemical load, but also by food. The highest concentration of HPL in the urine is usually found several hours after a hot meal. Alcoholism, hyperthyroidism (increased thyroid processing) and mononucleosis (infectious disease with lymph node swelling) can influence the outcome.

The following diseases and conditions may increase the rash: pernicious anemia, Bartter’s syndrome, liver cirrhosis, Crigler-Najjar’s disease, Gilbert’s disease, hepatitis, spherocytosis, malaria, sickle cell disease, shortly after a heart attack, physical stress, psychological stress and shortly after operation or accident. In these cases, there is not necessarily a false-positive result.

Fals negative results

Your result may be false negative if you have regularly used vitamins, in particular B vitamins, zinc or manganese, in the form of multivitamins or mineral supplements. Following the use of such supplements, the quantity of HPU excreted gradually decreases. It will increase again during the period in which you avoid these supplements before your test, but it may not be sufficient to provide a positive result.

In general it can be assumed that,  if you take more than 100mg of vitamin B6 over an extended period of time, you may expect a negative result, unless you are experiencing increased amounts of stress. Your result will also be lower if you needed to urinate several times the night before the test, or if you use diuretics (water tablets).

Very specific drugs can negatively affect the amount of HPL secreted. Anaemia from causes other than HPU, such as a deficiency in  vitamin B12, sickle cell anaemia and reduced bilirubin levels may also resilt in lower concentrations of HPL in the urine.