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Indian Journal of Dermatology, Venereology and Leprology
Medknow Publications on behalf of The Indian Association of Dermatologists, Venereologists and Leprologists (IADVL)
ISSN: 0378-6323 EISSN: 0973-3922
Vol. 69, Num. 5, 2003, pp. 362-363
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Untitled Document
Indian Journal of Dermatology, Venerelogy & Leprology, Vol 69, No.
5 ,Sept-Oct, 2003, pp. 362-363
Letters to Editor
Response by the authors
Sanjiv Grover
Department of Dermatology, Air Force Hospital, Agram PO, Bangalore - 560007.
India.
Code Number: dv03064
Sir,
I thank the respondent for his interest
in my work and his valuable comments. High culture positivity and a high
rate of detection of non-dermatophyte moulds (NDM) were the highlights of the
work.
An attempt was made to define the role of NDM. Was it purely a contaminant
or a primary pathogen causing primary invasion of the nail, as is emerging
in recent times? The stringent English criteria to delineate NDM as a primary
pathogen were, therefore, applied in the study.1 As mentioned
in the article, eight of the thirteen NDM isolated in the study fit these
criteria,
i.e. all KOH-positive isolates that cultured pure NDM without dermatophytes.
It is these eight (13.5% of the total isolates) that would, therefore, claim
their role as a primary pathogen. Though the culture positivity of NDM is
high, it still falls within the reported range. A combination of several
factors
might have contributed to high culture positivity rates: the drying procedure
of Milne, the English criteria and the procedure of paired culturing of samples
(in plain Sabouraud's Dextrose Agar, and Sabouraud's Dextrose Agar with chloramphenicol)
which were repeatedly subcultured. Of course, larger studies would help throw
more light
on this rather unclear and as yet controversial role
of NDM in onychomycosis. Since the study was
concluded in May 2001 and submitted for publication in
August 2002, we did not have the privilege of the
knowledge of the later study by Gupta et al quoted by
the respondent.2
It is true that a hot and humid climate would favor fungal
growth irrespective of the etiological agent, but studies have nonetheless
reported this milieu to favor the growth of NDM.3 NDM can affect
all nails, though admittedly the toenails are their main prey. We isolated
NDM from practically every nail, either in pure or in mixed cultures and in
some cases from multiple sites. There is no break-up to show apart from the
finding that DLSO pattern was the most common clinical pattern seen.
No mention either of associated cutaneous fungal infections
or of history of repeated attacks of tinea anywhere on the glabrous skin was
made simply because it was not within the ambit of the study. The study did
not deal with the clinical differentiation between dermatophyte and NDM infections
on the skin. It dealt solely with a particular clinical form of fungal infection,
viz. onychomycosis and the mycological agents responsible for causing this
condition, which obviously involved culturing the isolates.
Onychomycosis is frequently a source of distress to the patient
because of the unaesthetic look of the diseased nails as it is readily visible
to the onlooker. And it is here where I differ with the respondent in my suggestion
of a cosmetically conscious younger person (as compared to an older person)
being more motivated in seeking medical consultation for his diseased nails.
As already mentioned, this suggestion was in addition to the observation
that younger persons, more so soldiers, would be more prone to occupation related
subclinical trauma predisposing them to fungal infections of the nails.
The question of classification of onychomycosis is not so
vexed.4 Literature abounds in defining onychomycosis broadly as
any fungal infection of the nail plate. This includes yeasts and NDM in addition
to dermatophytes. Proximal superficial onychomycosis
is a recognized clinical subtype of
dermatophytosis and no new classification schedule is being
introduced herein. Candidal onychomycosis has three
recognized clinical variants and chronic paronychia is one of
them. Candida is a known primary pathogen of the nail
plate and not a secondary invader as suggested by
the respondent. In addition, presence of nail
dystrophy is not essential in this condition; only erosion of
the distal nail plate is, which was present in our cases.
In any case, candidal onychomycosis must never be confused with chronic mucocutaneous
candidiasis (CMC), which is a syndrome consisting of
persistent candidal infection of the skin, the nail and the
mouth. Only a few of these cases, when associated
with systemic infections, may represent a manifestation
of primary defect of the immune system. As already mentioned, patients with
systemic diseases were excluded from the study; and so did not include
any cases of CMC.
References
- English MP. Nails and fungi. Br J Dermatol 1976;94:697-701.
- Gupta AK, Ryder JE, Summerbell C. The diagnosis of non-dermatophyte mold
onychomycosis. Int J Dermatol 2003;42:272-3.
- Tosti A, Piraccini BM, Lorenzi
S. Onychomycosis
caused by non-dermatophyte moulds: Clinical features and response
to treatment of 59 cases. J Am Acad Dermatol 2000;42:217-24.
- Hay RJ, Moore M. Mycology
(Superficial and cutaneous mycosis). In: Champion RH, Burton
JL, Burns DA, Breathnach SM, editors. Textbook of dermatology. 6th ed. Oxford:
Blackwell
Science; 1998.
p. 1281-350.
Copyright 2003 - Indian Journal of Dermatology, Venereology & Leprology.
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