Porphyria cutanea tarda (PCT) FAQs

People with PCT commonly develop skin problems. They will NEVER suffer an acute attack.

In PCT the high level of porphyrins leads to photosensitivity. The following symptoms can all develop in areas of skin exposed to sunlight, especially on the backs of the hands and sometimes on the face:

• Blisters: which can rupture and forms sores.
• Sores: these may heal slowly and cause scarring.
• Milia: these are little white spots that raise off the skin surface
• Fragile skin, which is likely to graze or tear very easily, heal slowly and may scar.
• Excessive fine hair growth, especially on hands, cheeks and forehead sometimes occurs
• Discolouration of the skin on the face can present.
• Changes in skin pigmentation, either increased or decreased, can occur.

In addition to the skin problems, persistently dark urine may also be noticed.

While treatment will be tailored to individual circumstances, the concept remains the same, whatever the type (whether type I or II): (a) removal of any identified cause (trigger) if possible, and (b) treatment.

By removing or decreasing the PCT triggers, it may be possible to reduce the level of excess porphyrins that have accumulated in the body. Women on oestrogen treatments will be asked to stop taking them while the PCT is being treated. However, it may be possible to restart hormone treatment once the PCT is in remission.

Specific treatments that aim to also reduce porphyrin levels include:

• Low dose chloroquine or hydroxychloroqine (usually one tablet of either drug twice weekly). These drugs help to mobilise the excess porphyrin from the liver so that it can pass out of the body in the urine. It is important that only a small dose is used, as larger doses can cause acute illness.
• Venesection/phlebotomy may be possible if raised iron levels are found. This involves regularly removing a unit of blood, the same process as followed by blood donors. The body then uses excess iron to make new red blood cells, reducing the stores in the liver, and the skin problems subside. The PCT may recur a few years after treatment has finished.

If a patient cannot tolerate either of these two treatments, other options are available, although these are more complicated to administer.

Porphyrin levels may remain high for a number of months after treatment has been started. During this time, patients will remain photosensitive and should avoid exposing their skin to direct sunlight as much as possible, even sunlight that passes through window glass in a home or car. Protect skin from sunlight by wearing light cotton gloves, long sleeves and a hat. Not everyone will find this necessary or acceptable; adjust your clothing as it suits you.

Occasionally skin symptoms may get worse and the urine may go dark on starting treatment.

In addition to the skin problems, persistently dark urine may also be noticed.

What drugs are safe for people with PCT?

Drugs do not hold the same danger for those with PCT as they do for people with acute porphyrias, therefore they do NOT need to abide by the SAFE drugs list.

However, for PCT patients:

• Alcohol should be avoided.
• Oestrogens (natural and synthetic), which can be found in the combined contraceptive pill, HRT and prostate cancer treatments, are also to be used very carefully. They may provoke symptoms and should not be prescribed when PCT is active
• Low dose chloroquine is often used to treat PCT. However, it is important to note that higher doses can cause acute health problems and should be avoided.

In addition to the skin problems, persistently dark urine may also be noticed.

PCT is diagnosed by measuring porphyrins in samples of blood, urine and faeces. Each of these samples must be collected into a special darkened container which excludes light (wrapping the specimen container in tinfoil before collecting the sample will darken it sufficiently). Other tests, such as blood tests for liver function, glucose and iron levels may be undertaken to investigate for the conditions described above which are associated with PCT. Depending on the results of these tests, you may also be referred to see another doctor, for example a liver specialist (hepatologist).

It is rare for more than one member of a family to have PCT, but if other family members are affected with similar signs and symptoms they can be tested. Screening of family members who do not have skin problems is not generally required.

Dundee Cream is not included in the British National Formulary, however it is prescribable (endorsed ACBS [Advisory Committee on Borderline Substances]) on the NHS in the UK. It can be obtained from Tayside Pharmaceuticals:

Tayside Pharmaceuticals
Ninewells Hospital
Dundee
DD1 9SY
Tel: 01382 632052

Unfortunately, people cannot simply purchase Dundee cream as it is a medicinal product, rather than a cosmetic, and can only be provided with a prescription.

For most European patients the Beige and Coral pink are usually correct. Only those with very dark skin types need the Coffee. So a typical prescription is for “reflectant sunscreen (‘Dundee cream’) Beige and Coral Pink – 50 gram tube of each colour”.

Problems obtaining Dundee Cream in England

Some people in England are experiencing problems obtaining Dundee Cream on prescription. This has occurred since the NHS stressed that sunscreens should not be routinely prescribed. Dundee Cream is different to a normal sunscreen, as it is a large-particle-size reflectant sunscreen. So it should still be available. However, pharmacists in some areas report that they can no longer select sunscreen options on their systems. Patients are then referred back to their GP.

GP practices in some cases have to refer to a committee to be able to prescribe it.

There are definite misunderstandings about the process:

• A prescribed sunscreen for severe photosensitivity (EPP) is allowed. Nothing in the English NHS guidance has changed this.
• In the skin porphyrias, the problem is with visible light NOT ultraviolet. This is why normal commercial sunscreens do not help much.

Unfortunately, people cannot simply purchase Dundee cream as it is a medicinal product, rather than a cosmetic, and can only be provided with a prescription.

While this is problematic, our advice is to be persistent. You may need to ask your GP to refer the case to a committee to enable it to be provided.

The following document might be useful in trying to persuade GPs/ CCGs to prescribe:

• The British Association of Dermatology list of recommended ‘Specials’ (page 11) states that reflectant sunscreens are recommended for photosensitivity disorders http://www.bad.org.uk/shared/get-file.ashx?itemtype=document&id=1848

Mineral sunscreens containing zinc oxide and/or titanium dioxide offer a level of protection by providing a physical block to visible light. Generally, the larger the particle size, the greater the protection. So the creams that offer the greatest protection are likely to be thicker, messier and quite opaque (like Dundee Cream).

Our members have noticed some success with the following, although this is all trial and error and you may not find the same products work for you.

• Surf Mud natural zinc
• Invisible Zinc Broad Spectrum 50 SPF
• Neutrogena Sheer Zinc-Oxide Face dry-touch sunscreen 50 SPF