This site is intended for health professionals only

At the heart of general practice since 1960

Fungal infections

Consultant dermatologist Dr Mark Goodfield tackles questions from GP Dr Graham Archard on how to successfully manage recurrent infection

Consultant dermatologist Dr Mark Goodfield tackles questions from GP Dr Graham Archard on how to successfully manage recurrent infection

1 With so many patients having recurrent fungal nail infections, is treatment actually effective in the long term?

The most important factor is to get the diagnosis correct. Patients treated for recurrent fungal nail infections often do not have that problem but a primary skin disease affecting the nail.

Good examples would be psoriasis or lichen planus affecting the nail alone or in conjunction with a co-existing fungal nail infection.

Taking appropriate samples and confirming the diagnosis with mycology is extremely important, so that the fungus can be identified and the treatment targeted. Sometimes multiple samples of subungual tissue are necessary before infection can be excluded, but with accurate diagnosis and modern treatments, 80 per cent of fungal nail infection is cured.

If the patient has underlying primary inflammatory nail disease as well, the appearance of the nail is not going to be normal even when the fungus is eliminated; so if positive pre-treatment mycology becomes negative after treatment, but the nail remains abnormal, further investigation of the nail apparatus is essential.

There are some patients who do get confirmed recurrent nail infections. In most it is probably relapse of their original infection due to inadequate treatment or the presence of an underlying condition.

For example, patients with finger nail infection will often have toe nail infection too, so the length of treatment needs to be adjusted. Some other patients with finger nail disease have abnormalities of their circulation, such as Raynaud's phenomenon, that predisposes them to further infection.

The overall message is to get the diagnosis right, to treat appropriately and in those patients where there is good evidence of recurrent or relapsing nail infection, to consider what underlying problem is making it happen.

Rarely, true immunodeficiency may be associated with recurrent candidal nail disease, and nail infection in a child should be investigated.


Is there a simple rule of thumb to decide when to make the switch from topical to systemic antifungals?

Patients with infections in multiple sites on the skin, those with nail disease other than the most trivial distal nail infection, those with palmar or plantar infection, and those with tinea capitis need systemic therapy.


Is there any evidence for the treatment of vulvaginal candida with yoghurt? Is there any evidence-based effective treatment for women with recurrent vaginal thrush?

The use of yoghurt in the treatment of vulvaginal candida is based on the potential role of probiotics on the genital tract flora, and as inhibitors of yeast infection.

The 'good bugs' normalise the local environment by stimulating local immunity, and displace the 'bad bugs' which predispose to infection with organisms like candida. At least, that is part of the theory for their potential effectiveness. Hard evidence is limited but the theory is very well documented.

There are good clinical trials indicating the value of particular antifungal treatments for straightforward vaginal thrush, but with recurrent disease the evidence base is limited. It is important to document the diagnosis properly since many people with recurrent vaginal symptoms attributed to thrush do not in fact have that disease.

However, there clearly are many women who do have recurrent vaginal thrush and although there have been many suggested medications (including yoghurt, local and oral antifungals, and local antiseptics) there is no definitive evidence-based therapy.


Many patients insist that their guts are pathologically colonised with yeasts or fungi which cause pathological effects. Is there substance in this and, if so, what can we do about it?

This is another extremely contentious area. There is no good evidence that women with, for instance, recurrent vaginal thrush have abnormally and pathologically colonised bowel, but symptoms attributed to such colonisation are often vague, very non-specific and extremely difficult to prove.

There is very little good evidence in the context of cutaneous disease that there is any relevance in the presence of yeasts in the bowel. At a practical level, while it is possible to reduce the numbers of yeasts in the gut, it is not possible to eradicate them and there is no sensible approach that can be recommended.


Is there any evidence for the treatment of fungal and yeast infections with complementary therapies?

None that is convincing. Confirmed infections require appropriate conventional therapy, although I do have experience of glorious inactivity with no treatment resulting in the resolution of extremely symptomatic tinea cruris.


How long after a skin fungal infection has apparently settled should topical antifungals be continued? Is there good evidence for one preparation over another? Why do dermatologists use topical ketoconazole rather than clotrimazole in seborrhoeic dermatitis?

The duration of therapy with a topical antifungal depends on which agent you choose. Azole antifungals, such as clotrimazole or miconazole, are fungistatic in their action. As a consequence treatment needs to be continued for about two weeks after the signs of the infection have resolved.

Many patients do not do this, and relapse is extremely common because the fungus has been suppressed, rather than eliminated. If you treat for long enough with a fungistatic agent, then the fungus will die anyway, but part of the reason for recurrence of fungal infections is that they are never really eliminated by these agents.

Antifungals that have fungicidal activity, such as amorolfine or terbinafine, kill fungi much more rapidly. Consequently, treatment can be stopped after two weeks of continuous use in the case of tinea corpris or cruris and a week for tinea pedis.

There is good evidence that the allylamine antifungals work more rapidly than azole antifungals, and the treatment period is shorter, although the apparent cure rate after an appropriate period of treatment is the same. There is little data on relapse after such treatments, but this is likely to be the area where they differ.

As far as ketoconazole in the context of seborrhoeic dermatitis is concerned, dermatologists use this agent in shampoo or cream form because there is good evidence for its effectiveness in large-scale clinical trials.

It may well be that clotrimazole would be as effective but it has not been studied as intensively. In addition, there is no shampoo preparation that allows delivery of the active ingredient in the way that ketoconazole shampoo does.


Do probiotics play any part in the management of fungal infections?

There is good theoretical evidence, although less practical evidence, that probiotics can modify the cutaneous flora in a way that is beneficial for the management of certain infections, most particularly involving candidal yeasts.

Clinical evidence is very limited and there is certainly no large-scale study demonstrating that probiotics cure common cutaneous infections. The most investigated role is in the management of vaginal thrush where both oral and local use of probiotics has shown reductions in yeast levels and improved symptoms. They appear to be harmless and may be helpful.


Although there are numerous different types of fungi and yeast in clinical practice is this really only academic –or does it matter?

It does matter and often considerably. Many yeasts and certain fungi are commensal on the skin, while others are secondary pathogens (only causing infection when the skin or nail is already abnormal).

For example, candida in nail disease is almost always a secondary pathogen, so isolating it from an onycholytic fingernail does not necessarily mean that it is the cause of the problem. Many moulds, such as scopulariopsis, are again predominantly secondary pathogens. When they are found in nail samples, it is important to have a good look for the dermatophyte infection that is often the cause of the abnormal nail in the first place. Certain fungi, for instance Trichophyton tonsarans in tinea capitis, are usually epidemic. Finding a case of this, particularly in a school child, should prompt investigation of others in the family, as well as contacts at school that may also be infected. Failure to do this is often associated with relapsing disease, and a later discovery of further cases amongst the contacts.


What is your last-ditch stand for the patient who has recurrent fungal infections which reappear as soon as therapy stops?

The critical issue is to make sure the patient really does have recurrent fungal infection. Appropriate sampling before therapy is the best way of making this diagnosis. When faced with a patient who is said to have recurrent fungal infections, my response depends on the pattern of disease.

A common problem is a patient said to have recurrent groin infection. Often these patients will have negative mycological investigations, and have seborrhoeic eczema, rather than real recurrent fungal infection.

I have seen a similar presentation with psoriasis in the flexures. With nails, the problem is often the presence of an underlying abnormality, either inflammatory skin disease, such as psoriasis, or previous trauma producing damage to the anatomy of the nail. If the diagnosis is confirmed to be a recurrent fungal problem, identification of the fungus allows selection of the correct antifungal.

For dermatophyte fungi, this is terbinafine, with the duration of treatment adjusted to the clinical situation. Occasionally, longer-term therapy may be necessary, and for nail disease, where drug penetration may be poor, surgical removal of the affected nail, followed by further oral therapy may be needed.

There is some suggestion that predisposition to dermatophyte infection may be genetic, so there may truly be some individuals in whom infection is both recurrent and persistent as a consequence of disordered responses to the fungus.

Mark Goodfield is a consultant dermatologist at Leeds General Infirmary and Honorary Secretary of the British Skin Foundation

Competing interests None declared

What I will do now

Dr Archard comments on the answers to his questions

• The overriding message I am getting here is 'prove the diagnosis'. Skin and nail scrapings seem to be all-important!

• I am surprised that 80 per cent of fungal nail infections can be cured. This has not been my clinical impression, but I shall look again – particularly with a proven mycological diagnosis

• In the light of the poor evidence base for the treatment of recurrent vaginal thrush I shall suggest the use of yoghurt for those prepared to do so: after all, it might be messy but it is harmless!

• I shall ensure that the message gets across to my patients – continue treatment for two weeks after complete resolution of a fungal infection

• I am interested that there is little evidence for complementary therapy effectiveness in the treatment of fungal infections, and shall advise my patients accordingly

Dr Graham Archard is a GP in Christchurch, Devon

Take-home points Take home points

• With accurate diagnosis and modern treatments, 80 per cent of fungal nail infection is cured

• Azole antifungals are fungistatic and need to be continued for about two weeks after the signs of the infection have resolved

• Amorolfine or terbinafine are fungicidal and kill fungi much more rapidly, so they can be discontinued after two weeks in tinea corpris or cruris, and a week for tinea pedis

• There is good theoretical evidence, although less practical evidence, that probiotics can modify the cutaneous flora in a way that is beneficial for the management of certain infections

• Candida isolated in nail disease is almost always a secondary pathogen problem, as are many moulds

• Predisposition to dermatophyte infection may be genetically determined, so some recurrent and persistent infection may be because of a disordered response to the fungus

Rate this article 

Click to rate

  • 1 star out of 5
  • 2 stars out of 5
  • 3 stars out of 5
  • 4 stars out of 5
  • 5 stars out of 5

0 out of 5 stars

Have your say