Why do I have so many dark brown spots?

Q: I am 28 years old and have dark brown spots on my neck, on the back and near the armpits (each about 5 cm long). The dermatologist says that the skin has got damaged due to sun tanning but I hardly move in the sun. He prescribed me some anti-fungal cream and anti-allergic as well but nothing helped. Can you please tell me what could be the reason for these brown spots? Is it a sign of any inner organ disorder?

A:What you have is probably coloured or chromic pityriasis versicolor. This is a common skin disease caused by an overgrowth of the yeast fungus called Pityrosporum orbiculare (Malassezia furfur). Most adults have Pityrosporum orbiculare on their skin; however, in a few people its presence results in a harmless skin disease. Everyone gets Pityrosporum orbiculare on their bodies at some point in life. This causes the person no problems unless it starts to grow excessively. Little is known of why this happens, but pityriasis versicolor is very common in subtropical and tropical regions. It is liable to flourish during the summer in our country. Profuse perspiration and high production of sebum (oil) by the skin make it easier for the fungus to multiply and spread. Pityriasis versicolor is commonly seen on the upper part of the back and on the chest, but it can be found on the entire body. In summers the infection is seen as well-defined, uneven patches. The patches are pale-red or brownish, and scaly. The patches often merge into big blotches that may look like maps. Sunbathing evens out the colour and makes the condition less visible. In autumn the patches become scaly and change colour. In people who have tanned skin, this stage is quite visible as these patches appear white. It is at this point that most people first consult their doctor. People who suffer from profuse sweating or high production of sebum, for instance teenagers are at high risk to develop this condition. The condition is not contagious. Many other skin diseases that require a completely different treatment can cause the same symptoms as pityriasis versicolor, so it is very important that the doctors initial diagnosis is confirmed by tests. A scrape should be taken for microscopy and cultivation in a laboratory. Pityrosporum orbiculare gives out yellow-green when exposed to ultraviolet light (Woods light examination). The outbreaks are treated with selenium sulphide shampoo, or ketoconazole shampoo or cream. Selenium shampoo is applied to the body and rinsed off after 30 minutes every day for a week. Ketoconazole shampoo is used to wash the body for five minutes once daily for five days. In severe cases, the doctor may choose a treatment with itraconazole capsules. This treatment should also be followed up with preventive treatments in the subsequent year. Pityriasis versicolor can be prevented from reappearing by washing with either selenium sulphide shampoo, or ketoconazole shampoo. Talk to your doctor about this. The condition is likely to recur, so it is recommended that the preventive treatment is started in the spring. In some people, Pityrosporum orbiculare infects the hair follicles on the back and on the chest, which causes highly itchy acne-like spots to appear. This condition is called pityrosporum folliculitis, and it is more common in people who are between 30 and 40 years of age, particularly women. A treatment with itraconazole capsules will make the symptoms go away. Treatment of the first outbreak will quickly prevent the condition from developing further. However, the white patches will remain for a couple of months until the skin has renewed itself. Preventive treatment in subsequent summers can stop the white patches from reappearing.