
Notable
Case
Acute and recurrent skin ulceration
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Introduction | Spider bite is the single commonest reason for inquiries to
the Victorian Poisons Information Centre, with over 1300 calls
recorded in 1997.1
Most people with spider bite require no specific treatment and
suffer only minor symptoms, but a small number develop necrotic
skin lesions associated with significant morbidity.2-4
One series reported no significant illnesses in 36 bites,5
and only seven definite cases of skin necrosis after spider bite
have been published in Australia.3,4,6,7
This paucity of reports has led to debate as to the ability of
Australian spiders to cause skin necrosis (necrotising
arachnidism).
We performed a retrospective analysis of case records of suspected necrotising arachnidism in Australia to better define its clinical features and to compare it with loxoscelism, a well-recognised cause of skin ulceration in the Americas.
|
||||||
|
|
|||||||
| Methods | Patients were identified from records of inquiries from
clinicians between January 1992 and July 1998 held by the
Australian Venom Research Unit and cases referred to the
Hyperbaric Unit of the Alfred Hospital, Melbourne. Initial
case-finding criteria were a history of spider bite with
subsequent ulceration or necrosis at the bite site. Only cases
in which both the patient and primary treating doctor were
contactable by telephone were included (with the informed
consent of both patient and doctor).
In the patient interview we asked for demographic details, the method of identification of the spider, details of ulcerative or necrotic lesions and any other related problems, treatment, outcome details and relevant past medical history. This information was confirmed with the patient's doctor, who was also asked about details of investigations, treatments and outcomes.
|
||||||
|
|
|||||||
| Results | Fifteen cases were identified from more
than 600 patients with skin lesions but without confirmed spider
bite. In 14 cases (Box 1) the spider was
said to be a white-tailed spider (Lampona species) but
in only three cases was this identification confirmed. One
case involved two black house or black window spiders (Badumna
species; see Box 2).
All of the spider bites were to the limbs, and involved blistering, ulceration or necrosis of the skin. Thirteen were described as painful. Five patients experienced ongoing disability, and one required amputation of the hand and distal forearm. Four of the 15 patients experienced systemic symptoms (fever), and three had ulcers that were culture-positive for Staphylococcus species (one positive for Streptococcus species also). Nine patients had recurrent lesions, involving recurrent breakdown or blistering of the skin after healing, or breakdown of skin grafts used to treat non-healing ulcers. Oral or intravenous antibiotics (including doxycycline, penicillin or flucloxacillin) were given to 14 patients. Other treatments included dressings, antihistamines, topical and oral corticosteroids, hyperbaric oxygen therapy and skin grafting.
|
||||||
|
|
|||||||
| Discussion | A major difficulty in the clinical study of spider bite is
accurately identifying the spiders involved. Our series included
11 cases in which a spider was witnessed to bite the patient but
was not captured for identification, one case where the spider
was captured and identified by a clinician, and three cases
where the spider was captured and identified by an expert
arachnologist. White-tailed spiders are distinctive, but in most
of these cases absolute attribution to Lampona is not
possible. Window spiders are relatively nondescript, and
therefore less likely to be correctly identified unless captured
and formally identified by an arachnologist.
Four cases of skin loss attributed to bites from Lampona have been previously reported.3,4,7 Two of these (Cases 54 and 137) are included in this study, as both patients were reported to the AustralianVenom Research Unit independently. Several cases of bites from Badumna species have been published. These patients mostly experienced significant sickness, without skin loss.2,8 Some skin loss was reported in the case of a male black house spider bite.6 The case presented here (Box 2) is the first to link the female spider to skin necrosis. It has been suggested that many cases of suspected necrotising arachnidism in Australia may be the result of bites from spiders of the genus Loxosceles, a group associated with necrotising arachnidism on several continents.9 While it is probable that some Australian cases of necrotising arachnidism might be attributed to this spider, it would be difficult to implicate Loxosceles in the cases reported here. The lesions reported in this series show similarities but also significant differences from those caused by Loxosceles. As with Loxosceles, the initial bite appears to be relatively painless, with pain developing over the next 12-24 hours, accompanied by local erythema and oedema, then blister formation and ulceration.10 However, Loxosceles produces a deep ulcer, with a rolled edge and necrotic base, extending into and sometimes through subcutaneous fat to expose underlying muscle.10,11 By contrast, most ulcers reported here were superficial, being confined to the epidermis and dermis. Another important difference appears to be the site of bites that progress to significant ulceration. Significant Loxosceles lesions occur in areas of abundant subcutaneous fat, with involvement extending beyond the margins of the skin necrosis.11 The lesions reported here occurred in areas of little or no subcutaneous fat. An infectious aetiology has been proposed for necrotising arachnidism in Australia,12 but the concept that Mycobacterium ulcerans might be such an agent13 was subsequently challenged.14 Bacillus, Staphylococcus and Penicillium species have been cultured from several spider venoms, including that of a Lampona species.14 Only three of the 15 patients in our series had ulcers which grew any microorganisms, but, as 14 patients had been treated with antibiotics, infective organisms may have been cleared before cultures were prepared. However, the absence of cultured organisms and poor clinical response to antibiotic therapy seen in many patients suggests that this condition is more complex than simple skin infection. Nine of the 15 patients in our case series had recurrent ulceration. This problem had not been reported in Australia until very recently.7 There are several American reports of lesions attributed to Loxosceles that have resulted in chronic non-healing ulcers and recurrent ulceration. These were felt to be secondary to induction of a pyoderma gangrenosum-like disease process.15 Pyoderma may follow a minor injury and may be aggravated by surgery.16 It is typically associated with systemic immune abnormalities, but up to 50% of cases are described as "idiopathic". Spider bite may act as a trigger to precipitate this condition in susceptible individuals. Several patients in our case series had histological findings consistent with pyoderma, and surgical intervention may have been associated with a poorer outcome. Although no patient in this series received corticosteroids at the doses recommended for pyoderma, long term topical corticosteroids may have slowed progression of the lesion in case 14. Prospective study of the value of this treatment in cases of necrotising arachnidism should be considered. Management of necrotising arachnidism remains an area of debate, and there is limited information upon which to make recommendations for the Australian situation. At least for Loxosceles envenomations, conservative management appears to be the best primary treatment. This should include tetanus prophylaxis and routine wound care. Early ice water application to bites is recommended to counter inflammation. Initial studies proposed early excision and grafting of ulcers,11 but more recent experience suggests that this may worsen the lesion and delay healing.17 Hyperbaric oxygen therapy is gaining popularity in general wound management. Animal models have produced conflicting results on the value of this type of treatment for Loxosceles lesions.18,19 Treating ulcers attributed to Lampona bites with hyperbaric oxygen therapy appears to have a marked clinical benefit.4
|
||||||
|
Acknowledgements |
|||||||
| We thank Mr Albert Ong, of the Pathology Department, Gladstone
Base Hospital, for permission to reproduce his photograph of a
patient, Dr Robert Raven and Mr Phil Lawless of the Arachnology
Department of the Queensland Museum, and Ms Catriona McPhee and
Dr Ken Walker of the Museum of Victoria for spider
identification and photographs, and Dr Ian Miller, Director of
the Hyperbaric Unit at the Alfred Hospital in Melbourne, for
assistance in collecting patient information. This study would
not have been possible without the assistance of the many other
clinicians and patients involved. We thank the Victorian
Department of Human Services, CSL Limited, BHP Community Trust
and Snowy Nominees for financial support, and Dr Anna Young and
Dr Tony Pennington for helpful discussion.
|
|||||||
|
|
|||||||
|
|||||||
|
|
|||||||
| References |
(Received 19 Oct 1998, accepted 1 Jun 1999)
|
||||||
|
|
|||||||
| Authors' details | Australian Venom Research Unit, Department of
Pharmacology, The University of Melbourne, VIC. Steven J Pincus, MB BS, BSc(Hons), Research Registrar. Kenneth D Winkel, MB BS, FACTM, Director. Gabrielle M Hawdon, MB BS, MPH, Deputy Director. Struan K Sutherland, MD DSc, Honorary Principal Fellow. Reprints: Dr K D Winkel, Australian Venom Research
Unit, Department of Pharmacology, The University of Melbourne,
Parkville, VIC 3052. ©MJA
1999
Readers may print a single copy for personal use. No further reproduction or distribution of the articles should proceed without the permission of the publisher. For permission, contact the Australasian Medical Publishing Company. Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia <http://www.mja.com.au>". <URL: http://www.mja.com.au/> © 1999 Medical Journal of Australia. We appreciate your comments.
|
||||||
|
|
|||||||
|
|||||||
| Back to text
|
|||||||
|
|||||||
|
|||||||
| Back to text
|
|||||||
| The Links Below Jump To Pages On Whatever Web You Are In | |||
| Table Of Contents | Search This Web | Navigation Help Page | |
| Write To Karl Loren -- He Pledges To Answer EVERY Personal Message, Personally. Click here or on his name in the box below. | |||
| The Links Below Are To Various Web Sites Published By Karl Loren | |||
| Karl Loren Web | Vibrant Life Web | Karl Loren's Book | |
| Super Colostrum | Bulk MSM | Heart Disease | |
| Emmessar | Happiness | Arthritis | |
| Instead Of | Chelation Therapy | Super Colostrum (2) | |
| Karl Loren's Catalog Store | Central Page For All 12 Webs! | ||
|
I promise to answer your message -- click here to send me a personal message
|
|
SUBSCRIBE: The Wednesday Letter is a free electronic monthly newsletter written and published by Karl Loren. You can view more than 50 back issues of this publication by clicking here. The Wednesday Letter subscription list is maintained on a secure server, no name is ever given or sold to anyone, and it is never used except for this Newsletter. It is automatically published on the Tuesday night just before the first Wednesday of every month. You can subscribe to this free monthly electronic letter by entering your eMail address and name below. You will then automatically receive a request for confirmation, sent to whatever address you have entered. If you do NOT receive this confirmation request, then you will not be subscribed. There may have been an error with your address and you should resubmit. The letter is never sent twice to the same address -- so you do not have to worry about a duplicate subscription. When you receive this confirmation request you must reply to it, or your subscription will not become active. No one can subscribe your name, and address, without you being notified, and if you get an unwanted notice of subscription you only need to DO NOTHING and the subscription will NOT be active.
REMOVAL: You can remove yourself from the subscription list in several different ways. Click here to read about this entire newsletter system. Every edition of The Wednesday Letter is delivered to your address with YOUR name and address in view on the letter, with a link that allows you to remove THAT name from the subscription list. If you try to send this removal message from an address different from the one you used to send in your original confirmation, then you will get a warning notice first, sent to the subscription address, asking you to confirm that you want to be removed from the list -- by replying to THAT request for confirmation, you will then be automatically removed. Thus, no one else can unsubscribe you, from some other computer, without your knowledge. But, if you send in the unsubscribe notice from the same machine used to receive the Letter, then the removal from the subscription list is automatic.
Personal Message: When you send a personal message to Karl Loren, you will receive a personal reply as per his instructions. Karl pledges that every personal message will get a personal answer. When you provide your mail address, we will send you free information including our free catalog and a cassette tape lecture by Karl Loren about heart disease, no charge, by mail, even if outside the US. You can select particular information you would like to receive, along with the free cassette tape and catalog.