The therapy is effective if done well, but the pediculosis does not give permanent immunity, consequently the possibility of new episodes remains high.
My 8 year old daughter has had head lice many times over the past few months. I have tried several treatments, but we can’t solve the problem. What can be done?
He answers Stefano Cambiaghimedical director, Pediatric Dermatology Unit, Maggiore Policlinico Hospital, Milan (GO TO THE FORUM)
The pediculosis of the capillitium due to louse of the variety capitis, a bloodsucking insect found throughout the world. The transmission of the infestation takes place for human-to-human contact, mostly head-to-head, although indirect transmission is possible, through objects that act as vectors for the parasite. The length of the hair is a factor favoring the development of pediculosis, which in fact has higher incidence in women. Treatment based on the correct use of an effective insecticide. Considering that it is a skin disease only (lice do not carry other diseases), in cases of correct routine use topical therapies. The cure makes use of neurotoxic products for the insect such as malathion, permethrin, carbaril and substances derived from pyrethrum (pyrethrins). These are compounds that are lethal to the adult parasite, but usually have little activity on eggs (nits). therefore always recommended the repetition of the treatment after a weekgiven that the nits open 6-8 days after their deposition.
Why therapy can fail
In recent times the availability of local non-pharmacological therapies has increased, but rather a suffocate the louse with more or less natural products. These therapies, which would have the advantage of less toxicity, usually require more numerous and accurate applications. Factors that influence the effectiveness of a product are its pediculicidal and ovicidal activity, its concentration, duration, quantity and method of its application on the scalp, the frequency of application itself and the formulation (for example cream or shampoo). Hats, scarves, combs, brushes, pillow cases should be isolated in a plastic bag for about ten days, or dry cleaned or 60. The use of insecticides for the treatment of furnishings and clothing and to disinfect the domestic environment is not recommended. Sometimes, despite a correctly performed therapy, pediculosis persists, becoming a cause of anxiety and frustration for parents. The causes of therapy failure can be various: a diagnosis error (it is not about pediculosis); the child’s poor adherence to therapy; the use of an ineffective therapeutic device; an inadequate, incorrect or incomplete dosage of the product; a re-infestation.
If the wrong diagnosis
The latter is a frequent occurrence: pediculosis does not leave permanent immunity, therefore the possibility of acquiring the parasitosis again from family members, friends, classmates remains very high. While it is true that children should not be treated in the absence of a certain diagnosis, the processing of affected contacts is mandatory to make the therapeutic intervention sensible and effective. Close contacts of patients should be carefully monitored and possibly undergo therapy. The misdiagnosis of pediculosis, however, is less rare than you think: in particular the so-called pseudo-nits or hair casts, keratin sleeves arranged along the pilar shaft, are often the cause of error. Even more frequent is the misdiagnosis in case of persistence of non-viable nits after performing a treatment not accompanied by the detachment of the eggs from the hair shaft. Non-viable nits must be removed with a dense comb. Finally, remember that there is no transmission of pediculosis between men and pets.
June 25, 2022 (change June 25, 2022 | 17:46)