ARTICLE
Auteur(s) :, Zahra Safaee Naraghi1, Parvin
Mansouri2, Mohammadreza
Mortazavi3,*
1Department of Pathology, Razi Hospital, Tehran
University of Medical Sciences, Tehran, Iran
2Department of Dermatology, Imam Khomeini Hospital,
Tehran University of Medical Sciences, Tehran, Iran
3Department of Surgery, Wound Healing Research Group,
University of Alberta, Edmonton, Alberta, CanadaFax: (+780) 492
6361.
accepté le 6 Août 2004
Sulfur mustard as a chemical weapon was first used by the Imperial
German Army against the Allied forces on the Western front, in July
1917 at Ypres, and since then this warfare agent has been named
yperite [1, 2]. Sulfur mustard has been used in different conflicts
during recent decades, including the Iran-Iraq war in the 1980s.
There are two types of mustard gas: sulfur mustard and nitrogen
mustard, both are synthetic and have structural similarities.
Contrary to sulfur mustard (yperite), nitrogen mustard has been
utilized as a chemotherapeutic agent [3] and has never been used
for chemical warfare [2]. Mustard gas is an alkylating agent and
its cytotoxic, mutagenic and carcinogenic effects are caused by
alkylation of DNA and cell proteins [4]. Mustard gases are
lipophilic liquids that easily penetrate the skin and mucosal
surfaces. In human skin, 80% of the applied mustard gas evaporates,
and 20% penetrates the skin, 10% of which binds to the skin sites,
while the remaining mustard gas is absorbed systematically [4]. The
mean latent period is 4-5 hours. Skin is one of the most commonly
affected organs in mustard poisoning. There are numerous reports
about the systemic [2, 4, 5, 8-12] and the skin [6, 7]
manifestations of mustard gas exposure, but the histopathologic
features of skin lesions have not been fully investigated. We
studied the clinical and histopathologic features of acute
cutaneous lesions induced by sulfur mustard in 32 Iranian fighters,
who were exposed to the agent in 1988.
Materials and methods
The patients were all male, with their ages ranging from 13 to 33
years (mean, 22). They were referred to Razi Hospital (the
dermatology center of Tehran University) because of their extensive
cutaneous manifestations. The mean of time from exposure till
admission in the ward was 4.6 days. The findings of complete
physical examinations of the patients were recorded in special
charts. The diagnosis of yperite poisoning was made only on the
basis of history and clinical findings. Routine laboratory tests
such as CBC, platelet, reticulocyte count and urinalysis were
performed for all of the patients. Other investigations including
serum level of ALT and AST, stool OB, skin lesions and (or) blood
cultures were carried out whenever clinically indicated. Skin
biopsies were obtained from all of the patients, and smears of
blister content were prepared in 18. The mean of time from exposure
until when the biopsy specimens were taken, was 5 days. Tissue
specimens were fixed in formalin, dehydrated, embedded in paraffin,
sectioned and stained with hematoxylin-eosin, and periodic
acid-Schiff (PAS) to evaluate basement membrane and ground
substance; trichrome for collagen fibers; acid orcein for elstic
fibers; and Fontana-Masson to study melanin and its distribution
within the epidermal layers. All of the smears taken from blister
contents were stained with Giemsa.
Results
The mean exposure period was less than one hour for many of the
patients (34.4%), and few patients were exposed for more than six
hours. The latent period was less than six hours in the majority of
the patients. The most common clinical presentations were cutaneous
(100%) (perhaps because of selective referral of the patients),
neuropsychiatric (81.2%); ophthalmologic (71.9%), respiratory
(68.7%), and gastrointestinal signs and symptoms (65.6%). Severity
of the skin manifestations depends on concentration of the agent,
duration of exposure, body site of exposure, environmental
temperature and humidity, and the use of protective suits and face
masks. The main cutaneous complaints of the patients were pruritus
(96.8%), burning sensation (96.8%) and pain (table 1)( Table 1 ). Involvement of the skin at the flexural
areas (groin and axilla) was more common due to the moisture and
occlusion effect, leading to increased absorption of the chemical
agent. Involvement of the skin in the genital area (38.7%) ( (figure 1A) ) was more
frequent than the face (32.3%) and the axilla (25.8%). The most
common cutaneous findings were erosions (93.5%), erythema (83.9%)
and hyperpigmentation (83.9%) ( (figure 1B and C) ). Other
frequent findings (table 1) were vesicles, bullae ( (figure 1A) ), ulcerations
( (figure 1B) ),
edema and hypopigmentation. The most significant laboratory
findings in some of the patients were: mild anemia (30%), increased
ESR (33.3%), elevated ALT and (or) AST (30%), and leukocytosis
(13.3%). A few cases showed mild thrombocytopenia, bilirubinuria,
hematuria, proteinuria, urobilinogen in urine and positive stool
OB. Positive bacterial culture of the skin lesions (coagulase
negative and positive staphylococci) was found in 3 cases and
positive blood culture (pseudomonas and staph. aureus) were
detected in 2 patients (table 2)( Table
2 ).
Table 1 Symptoms and signs of acute cutaneous lesions
in studied victims of yperite poisoning
|
Signs and symptoms
|
Frequency (Number)
|
Percentage (%)
|
|
Symptoms:
|
|
|
|
Pruritus
|
30
|
96.8
|
|
Burning sensation
|
30
|
96.8
|
|
Pain
|
24
|
77.4
|
|
Signs:
|
|
|
|
Erosion
|
29
|
93.5
|
|
Erythema
|
26
|
83.9
|
|
Hyperpigmentation
|
26
|
83.9
|
|
Vesicle
|
25
|
80.6
|
|
Bulla
|
24
|
77.4
|
|
Ulceration
|
22
|
71
|
|
Edema
|
9
|
29
|
|
Hypopigmentation
|
7
|
22.6
|
Table 2 Paraclinical findings in studied victims of
yperite poisoning
|
Laboratory findings
|
Frequency (number)
|
Percentage (%)
|
|
Increased ESR
|
10
|
33.3
|
|
Mild anemia
|
9
|
30
|
|
Increased ALT and (or) AST
|
9
|
30
|
|
Leukocytosis
|
4
|
13.3
|
|
Bilirubinuria
|
4
|
10
|
|
Mild thrombocytopenia
|
3
|
10
|
|
Urobilinogen in urine
|
3
|
10
|
|
Positive culture of skin lesions
|
3
|
10
|
|
Positive blood culture
|
2
|
6.6
|
|
Leukopenia
|
2
|
6.6
|
|
Hematuria
|
1
|
3.3
|
|
Proteinuria
|
1
|
3.3
|
|
Occult blood in stool
|
1
|
3.3
|
Histopathology
The histopathologic findings of the acute skin lesions induced by
mustard gas are summarized in table 3( Table
3 ), and include the following features
Epidermis
Hyperkeratosis (75%), parakeratosis (40.6%), hypergranulosis,
hyperplasia, atrophy, necrosis, vesicles and bulla ( (figure 2A) ), with various
contents of fluid and cells, were observed. Other less common but
significant findings were apoptosis ( (figure 2B) ), acantholytic
cells and multinucleated giant cells in the epidermis, and cellular
atypia (i.e. increased nuclear size with hyperchromasia and
polymorphism in a wide range of severity) of the epidermal cells (
(figure 2B) ).
There was variation in the thickness of the basement membrane below
the basal layer in sections stained with PAS. Disruption of the
basement membrane was noted in several areas. Other epithelial
changes included vacuolar changes of basal cells ( (figure 2C) ) and increased
mitosis in 31.3% of the specimens. Hyperpigmentation of the basal
layer, an increased number of clear cells (melanocytes), and
transportation of melanin pigments into higher layers of the
epidermis (53.1%) could clearly be seen with Fontana-Masson
staining ( (figure
2D) ).
Table 3 Main histopathological findings of acute
cutaneous lesions in studied victims of yperite poisoning
|
Histopathologic finding
|
Frequency (number)
|
Percentage (%)
|
|
A. Epidermis:
|
|
|
|
Hyperkeratosis
|
24
|
75
|
|
Hypergranulosis
|
12
|
37.5
|
|
Parakeratosis
|
13
|
40.6
|
|
Necrosis
|
9
|
28.1
|
|
Atrophy
|
9
|
28.1
|
|
Acantholysis
|
3
|
9.3
|
|
Hyperplasia
|
18
|
56.3
|
|
Atypical changes
|
14
|
43
|
|
Vesicle and bulla
|
16
|
50
|
|
Vacuolar degeneration of basal layer
|
23
|
71.9
|
|
Hyperpigmentation of basal layer
|
17
|
53.1
|
|
Increased mitosis in basal layer
|
10
|
31.3
|
|
B. Dermis:
|
|
|
|
Inflammatory changes
|
14
|
43.8
|
|
Edema and ectasis of blood vessels
|
19
|
59.4
|
|
Collagen fiber changes
|
25
|
78.1
|
|
Eccrine gland changes
|
20
|
62.5
|
|
Hair follicle changes
|
27
|
84.4
|
|
C. Hypodermis:
|
|
|
|
Connective tissue thickening
|
17
|
53.1
|
|
Blood vessel wall changes
|
10
|
31.3
|
|
Prominent inflammatory changes
|
7
|
21.9
|
Dermis
Dermis showed vascular dilatation (telangiectasia), perivascular
edema, and mild to moderate infiltration of predominantly
mononuclear cells (43.8%), vascular damage, endothelial swelling
and extravasated erythrocytes ( (figure 3A) ). There was no
histologic evidence of vasculitis. Low grade fragmentation of
elastic fibers and loss of regular arrangement of the collagen
bundles and homogenization ( (figure 3B) ) were clearly
visible with H&E, trichrome and elastic staining. Skin adnexae
showed increased thickness in the basement membrane of sweat glands
and hair follicles ( (figure 3B) ). The quite
different changes of the secretory part of the apocrine glands
included hypertrophy and occasionally atrophy of the luminal cells.
The follicular structure revealed low grade perifollicular
fibrosis, the presence of mononuclear inflammatory cell infiltrate
around the hair follicles with focal destructive changes ( (figure 3C) ).
Hypodermis
Hypodermis showed occasional non-specific changes including mild
inflammation of connective tissue septa and thickening of small
vessel walls.
Discussion
The clinical and paraclinical findings of acute sulfur mustard
poisoning have been reported in several publications [2, 4, 5,
9-11], but there are few reports concerning the histopathologic
features of acute mustard-induced cutaneous lesions [10-14]. The
widespread erythema, detachment of epidermis, confluence of
vesicles leading to large flaccid bullae and positive Nikolsky sign
in skin lesions closely resemble toxic epidermal necrolysis (TEN)
[10]. The presence of a large accumulation of melanin in all layers
of the epidermis, even in the horny layer, and also numerous
melanophages filled with coarse melanin granules in the upper
dermis were described as being due to enhanced melanogenesis in
melanocytes by a direct stimulus of mustard gas [10]. Vossaert et
al. [12] explained epidermolytic lesions, subepidermal bullae,
densification of connective tissue in superficial dermis and loss
of typical palisade structure of the basal cell layer in cutaneous
lesions. Coppens et al. [13], showed widespread exfoliation of the
epidermis, normal adnexae in the underlying dermis and nearly
normal hypodermis in histopathologic autopsy findings of a mustard
gas victim referred from Iran. Pierard et al. [14] recognized
several groups of alterations in cutaneous lesions in mustard gas
casualties. These alterations involved the keratinocytes and the
melanocytic system. They also found dermal changes and epidermal
hyperplasia with or without atypia. The histopathologic changes of
skin induced by mustard gas could be described in four patterns:
- 1. Interface dermatitis with or without necrosis
(vacuolar type and lithenoid type): Vacuolar degeneration of basal
cells and necrosis of the epidermis resembling toxic epidermal
necrolysis (TEN) or erythema multiforme were seen in this
pathologic pattern. The sequence of hyperpigmentation at the
blister roof, acceleration of pigment transport from melanocytes to
surface keratinocytes and finally exfoliation of the epidermis
could explain marked hypopigmentation following improved bullous
lesions.
- 2. Spongiotic dermatitis and bullous dermatitis:
spongiotic dermatitis included microscopic findings of acute
contact dermatitis, subacute or chronic eczema. The bullae were
predominantly at the dermo-epidermal junction, and contained
clusters of inflammatory cells with or without acantholytic cells.
There were signs of cellular atypia, loss of normal cell
arrangement, and increased mitosis at the areas of cell
regeneration: mainly the floor and margins of blisters.
- 3. Pigmentary disorder pattern: irregular
hyperpigmentation of the basal layer and pigment-laden macrophages
in the upper dermis were observed in this pattern.
- 4. Other alterations of the dermis and hypodermis:
coagulation necrosis of the collagen bundles, low grade fibrosis
with a sclerodermoid appearance, telangiectasia and perivascular
infiltrate, without evidence of vasculitis. Finally, it can be
concluded that the histopathologic findings in mustard-induced
cutaneous lesions, regardless of the specific features due to
mustard effect, are consistent with the histologic changes of a
chemical burn.
Acknowledgments
We dedicate this article to the blessed memory of the great
dermatopathologist, Professor Amir Hossein Mehregan (deceased), for
his invaluable comments on this article and histopathologic aspects
of chemical war injury.
References
1 Hardman JG, Limbird LE. In: Goodman and Gilman, The
pharmacological basis of therapeutics. New York: Tenth Edition,
McGraw-Hill Publisher, 2001: 1389-94.
2 Barranco VP. Mustard gas and the dermatologist. Int J
Dermatol 1991; 30: 684-6.
3 Somani SM. In: Chemical warfare agents, First edition.
Academic Press Inc, 1992: 22-6.
4 Balali-Mood M, Navaeian A. In: Proceedings of the
Second World Congress on Biological and Chemical Warfare. Ghent
(Belgium). 1986: 464-73.
5 Thomsen AB, Eriksen J, Smith-Nielsen K. Chronic
neuropathic symptoms after exposure to mustard gas: A long term
investigation. J Am Acad Dermatol 1998; 39(1): 187-90.
6 Momeni AZ, Aminjavaheri M. Skin manifestations of
mustard gas in 14 children and adolescents. Int J Dermatol 1994;
33(3): 184-7.
7 Smith KJ, Hurst CG, Mooler RB, Skelton HG,
et al. Sulfur mustard: its continuing threat as a chemical
warfare agent. J Am Acad Dermatol 1995; 32(5): 765-6.
8 Somani SM. In: Chemical warfare agents, First edition.
Academic Press Inc., 1992: 16-8.
9 Balali-Mood M. In: Proceedings of the First World
Congress on Biological and Chemical Warfare. Ghent (Belgium). 1984:
254-9.
10 Requena L. Chemical warfare, cutaneous lesions from
mustard gas. J Am Acad Dermatol 1988; 19: 529-36.
11 Balali-Mood M. First report of delayed toxic effects of
yperite poisoning in Iranian fighters. In: Proceedings of the
Second World Congress on Biological and Chemical Warfare. Ghent
(Belguim). 1986: 489-92.
12 Vossaert K, Ceerts ML, et al. Dermatological
aspects of intoxication by mustard gas. In: Proceedings of the
Second World Congress on Biological and Chemical Warfare. Ghent
(Belgium). 1986: 511-3.
13 Coppens M, Roels H. In: Proceedings of the Second
Congress on Biological and Chemical Warfare, Ghent (Belgium). 1986:
542-52.
14 Pierard G, Dowlati A. Chemical warfare casualties
and yperite-induced xerodermoid. Dermatopathology 1990; 12(6):
565-70.
|
Version imprimable
Version PDF
