Manganism or manganese poisoning

Although manganese (Mn) is an essential nutrient, toxicity has been demonstrated in workers accidentally exposed to large amounts. Chronic exposure to Mn can damage the nervous system and respiratory tract and result in symptoms similar to Parkinson disease. to Mn are more likely to develop Parkinson disease than the rest of the population, especially at an early age.5 Mn has been shown to interfere with the absorption of Fe,6 with long-term exposure leading to Fe-defi ciency anaemia. Fe-defi ciency, on the other hand, can lead to brain Mn accumulation;7 and research has shown that dietary increases or decreases in Fe might contribute to brain deposition of Mn in populations exposed to Mn.8 Increased Mn also impairs the activity of the copper metallo-enzymes. Clinical stages of manganese poisoning Historically, three stages of manganism were described in workers with very high levels of Mn exposure.9 Stage 1 Very subtle symptoms. Individuals present with headaches, exhaustion, weakness and apathy. Symptoms can easily be confused with depression or other illnesses. Some researchers believe that this early stage is reversible.4 Stage 2 Individuals may present with short-term memory loss, impaired judgment, slurred speech, and even hallucinations. “Manganese madness” was the term used to describe the compulsive, strange behaviour of workers over-exposed to Mn in the Mn mines.10 Stage 3 Symptoms and signs of the last stage include involuntary muscle movements, tremors, poor coordination, a mask-like rigid face, and a staggering strutting gait. This stage is irreversible and may lead to complete disability. Removing a patient from exposure at this point does not seem to be helpful. In one report, the disease progressed over a 10-year period even after the patient was no longer exposed to Mn.11 It is important to note that the symptoms of manganism may appear any time from months to several years after an individual’s initial exposure to Mn.12,13