How can I get rid of this small rash on my tummy? And why am I getting palpitations?

Trouble spot

Trouble spot

Q. For the past three months, I have had a rash just above my bikini line and below my belly button. It is small and round and slightly itchy. When I was on holiday, spending most of my time in a swimsuit, it disappeared. But now that I am back in ordinary clothes, it has come back. Moisturising cream helps a bit, but I would like to get rid of it completely. A friend has suggested hydrocortisone cream, but I am not keen to use steroids.

A. I wonder if this is caused by an allergy to nickel. There is a notorious rash, similar to the one that you describe, that is caused by the metal stud button on jeans. The stud contains nickel, and it rubs on the skin, causing an allergic rash. Even if you have been wearing jeans for years with no problem, it is still possible that you have become allergic to nickel. Nickel allergy is surprisingly common, and many metals contain some nickel. If you wear jeans, I suggest that you cover the metal stud with a small piece of material. I would suggest that you use hydrocortisone cream for a short while. The amount of steroid in hydrocortisone is tiny, and it is an effective way of treating allergic rashes.

Racing heart

Q. I have been having short periods of palpitations recently. My pulse seems to speed up for a minute or so, and then slow down, for no obvious reason. It seems to happen mostly first thing in the morning or in bed at night. I have seen the doctor and had an ECG, which was completely normal. Needless to say, the palpitations didn't happen when I was attached to the ECG machine. When it happens, I feel slightly strange and afterwards I seem to pass much more urine. The doctor who performed the ECG was confident that it wasn't anything serious, but I am still worried as heart problems seem to run in my family.

A. Intermittent problems are often the most difficult to diagnose. Lots of people get palpitations, and often they are of no significance. But the fact that the palpitations make you feel "strange" and also cause you to pass more urine, makes me think that they may be significant. One way to help figure out what is going on is to have a 24-hour ECG monitor. Called a Holter monitor, this is a small portable device that monitors your heart over 24 hours. If the palpitations occur when the monitor is on, it will be possible to see exactly what is happening when the recording is analysed. The monitor is small and doesn't interfere with anything apart from swimming and bathing. Ask your doctor if a 24-hour Holter can be arranged. If this fails to pick up the palpitations, it may have to be repeated. Occasionally, a patient needs to be monitored for several days before the cause of the problem is found.

Boy trouble

Q. Our two-month-old son has one undescended testicle. This wasn't discovered when he was born, but it was picked up at the six-week check. The GP and health visitor felt this was likely to sort itself out, and we have been asked to come back when he is eight months old if the testicle has not appeared by then. Do undescended testicles usually descend without any help? Is it right to wait for six months?

A. Undescended testicles are not at all uncommon. If your son was born prematurely, this might explain why the testicle has not yet descended. But even in full-term boys, about three out of 100 will have one or both testicles undescended. About two-thirds of undescended testicles will naturally find their way into the scrotum by the age of nine months without any help. Testicles that are not in the scrotum by the age of one year will often need an operation to bring them there. Occasionally, a testicle that seems to be undescended is simply "retractile", ie sometimes it is in the scrotum, sometimes it seems to disappear upwards. These retractile testicles always sort themselves out without an operation. If your son's scrotum is fully developed on both sides, the testicle is very likely to come down without help. If one side of the scrotum is smaller than the other, the undescended testicle on that side is less likely to descend by itself. It's perfectly reasonable to wait until your son is eight months old. But if the testicle is still undescended, he should see a paediatric surgeon before he is one year old.

Have your say: readers write

Advice from BT and PJ of Middlesex on home blood-pressure monitors:

If someone has an irregular pulse, or arrhythmia, electronic home monitors are particularly inaccurate. For nearly everyone else, good-quality machines with an arm cuff are generally accurate.

I, too, suffer from white-coat hypertension and have monitored my blood pressure regularly for many years. I started home measurement when I realised that my blood pressure was in the normal range at home, but high whenever I visited the doctor. My doctor was initially sceptical about its accuracy, but on two occasions we compared readings in the surgery and the readings were virtually identical. Perhaps other readers should suggest to their doctors that they compare readings in the surgery to verify the accuracy of their home monitors. My instrument gave me early warnings of rising blood pressure which, of course, usually shows no symptoms.

Send your questions and suggestions to A Question of Health, 'The Independent', 191 Marsh Wall, London E14 9RS; fax: 020-7005 2182; or e-mail: Dr Kavalier regrets that he is unable to respond personally to questions