As many readers will no doubt testify, it can be a difficult and long drawn-out process before a set of symptoms finally becomes a diagnosis. In the early stages of a disease or when symptoms are atypical, the pathway of medical detection can be a somewhat tortuous one, writes Dr Muiris Houston.
But what about after a label has been put on your illness? Can you then move on to treatment and indeed to coming to terms with what may be a chronic condition?
Usually, of course, you can, but very occasionally there is a "diagnosis behind the diagnosis", as the following letter from a recently retired doctor suggests: "At age 75 I've recently been diagnosed with hereditary haemochromatosis. Looking back, I now see many of the signs that could have been a warning - provided any one of a number of doctors (including myself) had thought about the possibility.
"Even back in my 30s I used to get very tired in the afternoons; by my early 40s I had arthritis in my knuckles; in my 50s I started to get cardiac arrhythmias and had an enlarged liver; by 60 I had lost my axillary hair; at 70 I had early Dupuytren's contracture (a fibrosis of a tendon in the hand), and type 2 diabetes was diagnosed. Even then, no one had thought of haemochromatosis, and it wasn't until last summer, when I heard someone speaking about it on the radio, that I realised that his description of the condition applied equally to me. From then on, things have moved quickly to get my ferritin levels down. Incidentally, I show no sign of the classic textbook description of skin bronzing, but otherwise I think I'm a pretty typical case".
Hereditary haemochromatosis is a genetically-inherited condition in which excess iron is deposited in various organs, including the liver, heart and the pancreas. They eventually become fibrosed and their function deteriorates. Typical effects are cirrhosis of the liver, diabetes mellitus secondary to destruction of the pancreas and a swelling of the heart muscle called cardiomyopathy.
Known as the "Celtic disease" because of the high prevalence of the gene mutation in Europe, about one in 10 people here is a carrier, with an estimated one in 300 people affected by the condition. However, as our correspondent's story suggests, many of these remain undiagnosed.
The condition can be relatively easily detected by checking ferritin levels in the blood. Ferritin is a measurement of iron storage in the body. It can be altered in other disease processes, but nonetheless, it is a good general screening test for haemochromatosis.
Treatment is easy: the excess iron is literally bled out of the body. Once or twice weekly removal of 500ml of blood, for up to two years, usually does the trick. The ferritin level should drop progressively, and eventually it may be only necessary to have blood removed about three times a year as a preventative measure. So, for the person with diabetes, an enlarged heart, loss of axillary hair, unexplained enlargement of the liver or even arthritis, it is worth having a high index of suspicion for haemochromatosis. This is particularly important because treatment before there is organ damage can reverse the iron toxity and restore life expectancy to normal.
As our correspondent notes, he had no "skin bronzing", which was the classic sign of haemochromatosis taught to medical students. In fact, it is only present in cases with gross iron overload. He goes on to explain: "I've gone into all this detail because I'm now convinced that the medical professional generally doesn't appear to think about the possibility of hereditary haemochromatosis".
THERE is also a strong case for screening for the disease among all first-degree relatives. A simple ferritin test could prevent a huge burden of chronic disease if the condition was picked up and iron levels kept low throughout a person's life.
Less common, but another example, of a "hidden diagnosis" is alpha - 1 antitrypsin deficiency. Also an inherited genetic disorder, resulting in low or no levels of a protein in the blood (alpha-1 antitrypsin or AAT), it can lead to serious lung and liver disease. AAT is reckoned to affect 1,000 in the State - only 50 of whom have been diagnosed. The less obvious cases could include people with asthma which has been unresponsive to treatment or those with chronic obstructive airways disease whose origin is not obvious. Diagnosis of AAT is on the basis of a simple blood test.
I have no doubt that as medicine continues to advance, that we will see more examples of "the diagnosis behind the diagnosis".
Contacts: Alpha One Foundation, RCSI Building, Beaumont Hospital, Dublin 9. Tel: 01-4524341. Irish Haemochromatosis Society, The Carmichael Centre, North Brunswick Street, Dublin 7. Tel: 01-8388773; e-mail: irhaem@ hotmail.com
Dr Muiris Houston is at mhouston@irish-times.ie or leave a message at 01-6707711, ext 8511. He regrets he cannot reply to individual medical problems.