WHAT’S THAT ITCH?
Dr Sarah Jarvis gives us her advice
It’s worth pointing out that itchy skin is a symptom not a condition. Sometimes no cause is found, but it still creates significant irritation. If you have a rash to accompany the itching, your GP can often pinpoint the cause. But if not, blood tests may be needed to rule out anything serious.
Common triggers
Dermatitis is the medical word for inflammation of the skin. Eczema is a type of dermatitis, which usually starts in childhood but can persist for life. The most common type of eczema, atopic eczema, is linked to allergic tendencies and allergic conditions such as hayfever. There are two main types of dermatitis in adults. Allergic contact dermatitis is an intensely itchy reaction to even the smallest amount of whatever you’re allergic to; nickel in jewellery is the most frequent culprit, but other causes include cosmetic ingredients, latex, and chemicals such as hair dyes or strong adhesives.
More common is irritant contact dermatitis; the stronger the irritant (soaps, detergents, disinfectants, cement, even hard water), and the more often you’re in contact with it, the worse the symptoms. With the hand-washing and sanitisation of the past year, it doesn’t surprise me that I’ve seen a huge rise in patients complaining of sore, itchy, red hands. In addition, dry, hot (centrally heated), wet, cold or windy surroundings can all exacerbate itchy, dry skin.
If allergic dermatitis is at the root of your problems, you should avoid the slightest contact with the culprit substance for ever. You may need referral to a dermatologist for patch testing if the cause isn’t clear. For irritant dermatitis, frequent moisturising with an unscented emollient will help. Obviously you can’t stop washing your hands, and, for Covid-19 purposes, gentler ‘soap substitutes’, such as aqueous cream, aren’t recommended. However, if 60%+ alcohol-containing hand sanitiser is causing symptoms, try an alcohol-free hypochlorous acid alternative (speak to your pharmacist).
All-over irritation
It’s important to know that itching is rarely a sign of anything serious. However, itching all over, especially if it persists, needs checking out. That’s because, very occasionally, it’s the first
warning sign of a potentially serious underlying condition. Doctors divide the causes of itching into local (skin problems) and systemic (from elsewhere in your system). Possible systemic causes include diabetes, chronic kidney disease, underactive or overactive thyroid, iron deficiency, drug side-effects and, rarely, cancer, including Hodgkin lymphoma.
Liver problems
If you’re itching all over for no obvious reason, your doctor will also want to check how your liver is working. Your largest internal organ, the liver works tirelessly, helping to produce and process glucose, fats, proteins, carbohydrates, clotting factors and hormones; breaking down and disposing of toxins, waste products, medicines and alcohol; and storing vitamins and minerals. Produced by the liver, stored in the gallbladder and passed out into the gut, bile plays a vital role in digestion, especially of fatty foods. If its flow is blocked, you can develop jaundice, as bilirubin (a waste product from the breakdown of red blood cells, which builds up in your system) and bile salts can also build up in the skin, leading to itching.
Primary biliary cholangitis (PBC) is an autoimmune condition in which your immune system attacks your bile ducts, leading to raised levels of bilirubin and bile salts. Over time, this accumulation of bile can damage your liver cells, causing scarring and, in some cases, cirrhosis. It’s uncommon (affecting about one in 5,000 people in the UK) but nine in 10 people who develop PBC are women, mostly in their 30s-60s. Up to seven in 10 people with PBC will have generalised itching, which tends to be worse in bed at night.
Obstetric cholestasis (slowing down of bile flow during pregnancy) affects fewer than one in 100 pregnant women, but without treatment can lead to premature delivery or stillbirth. Itching all over is the most common symptom; if you develop itching while you’re pregnant, contact your doctor quickly.
The earlier liver problems are caught, the greater the range of treatment options available, so do speak to your GP. Even for autoimmune conditions such as PBC, newer targeted therapies are showing promise.
Fungal infections
Fungi live on our skin and usually do no harm, but if there are too many of them, the result is itching, redness and soreness. Examples include vaginal thrush, athlete’s foot, ‘jock itch’ (in the groin creases), and soreness under the breasts. What all these areas have in common is that they’re warm, moist environments, which is where yeast infections thrive.
Ringworm, despite its name, is not a parasitic worm but a fungal infection, which often affects the scalp. It spreads from person to person via skin contact or from infected clothing, towels or chairs, or sometimes from infected animals, and it causes an itchy red patch of skin with a red ring and pale centre.
Itching is one of the most prominent features of fungal infections. Treatment is with antifungal creams from your pharmacist (or GP, if the problem persists). But keeping the area cool and dry, with scrupulous hygiene, talcum powder and avoiding sweating, will reduce the risk of recurrence.
Thrush or something else?
Thrush usually causes genital itching and a cottage-cheese-like white vaginal discharge. But, occasionally, itching just outside the vagina – the vulva – is instead due to a condition called lichen sclerosus, which may have an autoimmune cause (where your body’s immune system turns on part of itself). It usually shows as itchy white spots on the vulva, which can be distressing.
Unlike thrush, lichen sclerosus does not extend into the vagina. However, over time, the white patches can merge together, leading to the skin becoming sore, fragile and prone to splitting. If untreated, the entrance to the vagina can become smaller, leading to painful sex. Do see your GP, as treatment with gentle emollients (rather than soap) and steroid cream can be highly effective.