is an ectoparasitic skin infection with the mite Sarcoptes scabei var. humanus. First described in 1687, with the organism responsible being identified in the 18th century, this intensely pruritic disease was named from the Latin word for: scratch “Scabere“.
Scabies affect people of all races and age groups and the geographic distribution is worldwide. It is spread by skin to skin, via both sexual and nonsexual , and in some cases as fomites.
Sign and Symptoms of Scabies
Patients with scabies complain of an intensely itching rash. The itching may be more severe at night and may affect any part of the body, but the most commonly affected areas are the inter-digital web spaces, axillae, genital area, buttocks, and breasts.
In the first attack of scabies, the symptoms do not occur for three to four weeks, till the patient is sensitized to the products of the mite. In subsequent attacks the symptoms may develop within few hours of infestation.
The patient presents with nocturnal itching, most marked when the person is warm in bed. It is associated with burrows, papules, papulo-vesicles, vesicles or pustules. Burrows, though considered pathognomic of scabies, are not frequently encountered in Indian patients. This is because they present late for treatment and by this time the burrows have been excoriated and the secondary bacterial infection has often supervened, resulting in impetiginization.
The distribution of lesions is characteristic and the sites of predilection are the inter-digital spaces of the fingers, palms, wrists, elbows, anterior axillary folds, lower abdomen, buttocks, nipple area in females, and external genitalia in the males. In infants and small children the scalp, face, palms, and the soles may also be involved. Very often, more than one member of the family may affected.
Pathophysiology of scabies
Scabies, a common cause of itching, is produced by infection with the mite Sarcoptes scabies varhominis. Poor hygienic conditions and overcrowding, permitting close body , favor the transmission of the disease.
Sarcoptes scabiei var. hominis is a mite, approximately 0.5 mm in length, that cause human scabies.
The female mite burrows under the skin and produces eggs and scybala. Acarus scabiei has four pairs of legs. The male is appreciably smaller. Acarus scabiei undergoes its life cycle on the skin surface. The male mite fertilizes the female and dies.
The adult female, after impregnation, burrows into the skin and forms and a tunnel in the horny layer (stratum corneum). It burrows at the rate of 1 to 5 mm per day. Two days after fertilization, it starts laying eggs along her course in the burrow. Two to the three eggs are laid each day.
A female Acarus lays a total of 10 to 25 eggs during her life span of 30 days and then dies at the end of the burrow. The egg hatches in 3 to 4 days producing a larva that moves to the skin surface. It then moults through various stages of octopod nymph into an adult mite in 10 to 14 days.
A type 4 delayed hypersensitivity reaction occurs after approximately 1 month in unsensitized patients or within hours in sensitized patients. This leads to the severe itching that is characteristic of scabies infection.
Diagnosis of scabies
It may take up to 6 weeks following exposure before symptoms of scabies infestation develop. In those who have been previously infected, symptoms can develop much sooner, sometimes within several days.
Infested person can transmit scabies to other prior to the development of symptoms. In those who are infected, pruritus eventually develops secondary to a hypersensitivity reaction to the mites and their secretion, eggs, and feces.
Lesions are most commonly found on the inter-digital web spaces, wrists, elbows, axillae, female breasts, and male genital areas. In typical scabies, patients usually develop red, raised papules.
Scabies is commonly misdiagnosed as other common skin conditions, such as eczema, drug reaction, impetigo, Folliculitis, atopic dermatitis, insect bites, and dermatitis. During scratching, skin lesions can become colonized and then infected with bacteria, such as staphylococcus or streptococci.
Burrows are often difficult to visualize because of excoriation. Skin scrapings should be done in all suspected cases, although the sensitivity of this test depends greatly on the experience of the examiner. Mineral oil should be placed upon a popular lesion or a burrow.
The involved skin is the scalpel blade and placed and placed on a glass slide. Under low power on the microscope, the examiner should search for mites, eggs, and fecal matter.
If scabies is suspected, the diagnosis can be confirmed by opening of a burrow or other skin lesion with a scalpel blade. The contents are placed on a slide, and a drop of oil is applied. Diagnosis is confirmed with identification of mites, eggs, or scybala (feces) on microscopic examination.
Complications of scabies
If untreated for several weeks or months, various complications can occur.
- Scratch dermatitis frequently of frank eczematous type.
- Bacterial infection
- Urticaria-occasional complication.
- Nummular dermatitis
- Glomerulonephritis in infants and children.
Treatment of Scabies
Because of resistance and neurotoxicity, lindane is no longer routinely recommended for the treatment of scabies. The currently recommended treatment for scabies is 5 % permethrin cream.
Permethrin is well tolerated but may cause burning stinging, or itching following application. Because of a lack of safety data, permethrin should not be used on those who are pregnant unless the diagnosis has been confirmed. The following plan should be followed when treating scabies:
- Immediately prior to treatment, all washable sheets, blankets, and personal clothes worn during the preceding week should be placed into a plastic bag, sealed, and sent to the laundry. These clothes should be washed in hot dryer. All non-washable personal clothes, such as shoes and jackets worn during the preceding week, should be placed in a plastic bag. These items should be dry cleaned or placed into a hot dryer for 20 minutes. If this is not possible, the bag should be scaled and set aside for 5 to 7 days.
- The person being treated should shower prior to applying permethrin. Hair should be washed, and fingernails and toe nails should be cut short. Permethrin should be massaged into the skin covering the entire body from the hairline to the soles of the feet. Medication should not the mucous membrane of the eyes, nose, or mouth. Scabicide should be applied under the fingernails and toenails.
- After applying permethrin, all towels and washcloths used by the inmate should be placed in a plastic bag and sent to the laundry for processing. Laundry staff should be advised to not sort these items and to wash and dry them separately from other laundry.
- Permethrin should be left on the body overnight and showered of the next morning. After permethrin has been washed off, bed lines, towels, and clothing should be changed again. The mattress, pillows, bedside equipment, and floors should be disinfected. Because they may be contaminated, all creams, ointments, and lotions used by symptomatic cases should be discarded.
Isolation of Patients with Typical Scabies
For a typical case of scabies, the infected inmate should be placed on isolation precautions in his or her assigned cell for the duration of the first treatment period (8 to 12 hours).
Isolation precautions can be discontinued after permethrin has been washed off. Patients who are being treated prophylactically need not be isolated.
Treatment of Crusted or Keratotic Scabies
Those with crusted scabies should be placed in isolation precautions in a private room until at least three negative skin scrapings have been documented and symptoms have resolved.
This may take weeks, depending upon the severity of the infestation. If permethrin is used, multiple treatments may be required for successful treatment of crusted or keratotic scabies. Crusts may need to be debrided to hasten eradication of infestation.
Homeopathic treatment of Scabies
Homeopathy is one of the most popular holistic systems of medicine. The selection of remedy is based upon the theory of individualization and symptoms similarity by using holistic approach.
This is the only way through which a state of complete health can be regained by removing all the sign and symptoms from which the patient is suffering.
The aim of homeopathy is not only to treat Scabies but to address its underlying cause and individual susceptibility. As far as therapeutic medication is concerned, several remedies are available to treat scabies that can be selected on the basis of cause, sensations and modalities of the complaints.
For individualized remedy selection and treatment, the patient should consult a qualified homeopathic doctor in person. There are following homeopathic remedies which are helpful in the treatment of scabies:
Mercurius Solubilis Hahnemanni
Silicea, Silica Terra
Squilla Maritima, Scilla