​Kembara Xtra - Medicine - Pediculosis

​Kembara Xtra - Medicine - Pediculosis 
An infectious parasitic disease brought on by ectoparasitic blood-sucking insects (louse)
Two types of lice infest people:
- The head louse (var. capitis) and the body louse (var. corporis) are two subspecies of the Pediculus humanus. Both species have three pairs of legs that join closely behind the head, are flat, wingless, and range in length from 1 to 3 mm.
- Pthirus pubis (pubic or crab louse): Has broad claws on the second and third legs and resembles a sea crab.
Systems impacted: exocrine and/or cutaneous
Synonym(s): crabs; lice

Epidemiology Incidence 6 to 12 million new cases annually in the United States  Head lice are most prevalent in children between the ages of 3 and 12; females are more likely than boys to contract them. Pubic lice are most prevalent in adults.
Prevalence
1-3% of industrialized nations have head lice.


Pathophysiology and Etiology 
The adult louse is dark grayish in color and runs swiftly, although it does not jump or fly.
- Eggs (nits) adhere to the base of the hair shaft (within 4 mm of the scalp) and blend in with the color of the host's hair.
- Nits, which are empty egg shells, are white (opalescent) and stay attached to the hair shaft.
- Lice pierce the skin, inject saliva (which has anticoagulant characteristics to allow for blood meal), and then consume blood as their sole source of nutrition.
It may take up to 6 weeks after the initial exposure for an itchy reaction to the feeding louse's saliva to manifest itself. It could take up to two days for symptoms to appear after a further exposure.
Transmission: direct touch between people
- Head lice: direct head-to-head contact or (less often) contact with fomite that has been infected
- Body lice: exposure to contaminated bedding or clothing
- Fomite transfer is far less likely than sexual transmission when it comes to pubic lice.
RISK ELEMENTS
Overcrowding and intimate personal touch in general
Head lice are more common in girls with longer hair who are in school.
African Americans hardly ever have head lice; hypotheses include twisted hair shafts and increased use of pomades. - Sharing combs, caps (including helmets), clothing, and bed linens.
Body lice: unsanitary conditions, homelessness
 Promiscuity (very high transmission rate)

Prevention 
Environmental precautions: Wash, dry-clean, or vacuum anything that may have come into contact with infected people.
Affected household contacts should be screened and treated.
Head lice: School nurses' follow-up care may help to stop recurrence and spread.
Limit your sexual partners to avoid contracting pubic lice (shaving your pubic hair won't stop it either).
 Body lice: good personal hygiene

Accompanying Conditions 

Up to one third of individuals with pubic lice also have a STI.

Pruritus is a common symptom that is frequently worse at night, and it is frequently linked to a "outbreak" in educational settings.
 Look into the contacts of sick people.

clinical assessment 
Visualizing live lice serves as confirmation of the diagnosis.
P. capitis (head lice) are most frequently seen behind the ears, on the back of the head, and on the neck (warmer locations).
There may be a role for eyelashes.
- Eggs that have been firmly embedded at the root of a hair shaft are challenging to extract.
- Small papules and localized erythema may accompany pruritus.
- Excisions around the hairline are possible.
- Inflammation and subsequent bacterial infections can result from scratching.
- In severe infestations, pyoderma and lymphadenopathy may develop.
Body lice (P. humanus) - Poor personal hygiene - Adult lice and nits in clothing seams - Severe itching in areas covered by clothing (trunk, axillae, and groin)
- Erythematous macules, papules, and wheals are the symptoms of uninfected bites.
- It's possible to see pyoderma and excoriation.
- Spread Rickettsia prowazekii (epidemic typhus), Borrelia recurrentis (louse-borne relapsing fever), Bartonella quintana (trench fever), and other pathogens.
Pubic hair is the most typical site for P. pubis (pubic lice), but lice can also infest anus, abdomen, axillae, chest, beard, eyebrows, and eyelashes.
- The root of hair shafts contain eggs.
- Anogenital pruritus - The surrounding skin may have blue macules.
- Groin infection and regional adenopathy may occur if therapy is delayed.

Differential Diagnosis Dandruff and other hair debris occasionally resemble head lice eggs and nits but are less adherent. Scabies and other mite species that can cause cutaneous responses in humans.


Laboratory Results 

The diagnosis is made after viewing a live louse.
To find live lice, thoroughly comb your hair with a fine-toothed louse comb (0.2 to 0.3 mm between teeth). To reduce static electricity, which keeps lice away, wet the hair. Simple eye inspection is just as sensitive as wet comb analysis, but it is only 25% as efficient.
Body louse: Check clothes seams for lice and their eggs.
A microscope makes it easier to see lice and their eggs.
Unlike dandruff, eggs and nits are more difficult to remove from a hair shaft.
Tests in the Future & Special Considerations
Even months after the active infestation has been eliminated, empty nits can still be found on hair shafts. Examined under a wood light, live nits glow white, while empty nits glow gray.
If you have pubic lice, check for STIs.

Management 

Clean things that came into contact with the sick person's head within the last 48 hours are considered to have head lice.
 Wash all clothing, towels, bedding, headgear, combs, and brushes in hot water (above 60 °C).
 Scrub the carpets and furniture.
 Place any personal items in a plastic bag and store for at least two weeks if they can't be dry cleaned, put through a hot water wash, or vacuumed.
 Concurrently examine and treat family members and close friends.
Sprays containing insecticide are not required.
Avoid sexual activity until all partners have received effective treatment for pubic lice.
Nit and egg removal: To avoid reinfestation, remove eggs that are less than 1 cm from the scalp. Eggs and nits stay in the scalp or pubic hair after shampooing or applying moisturizer until they are mechanically removed. Hair conditioner makes it easier to remove nits. - A fine nit comb works best for removing eggs and nits.

Medication 

Head lice treatments that are effective over-the-counter (OTC) include permethrin, synergized pyrethrin, spinosad, benzyl alcohol, malathion, and topical ivermectin.Malathion, permethrin, and synergized pyrethrin are efficient against pubic lice.
Permethrin is typically favored because it may continue to work for up to three weeks. Utilizing more recent shampoos and conditioners, however, can lessen the lasting effect.
Despite being second-line treatments for head lice, malathion and spinosad may not need a second application because of their ovicidal efficacy.
Both benzyl alcohol 5% lotion and ivermectin 0.5% lotion work well to get rid of head lice.

When treating head and pubic lice, the first line of defense is pyrethrum insecticides, such as permethrin 1% cream rinse (Nix) or pyrethrins 0.33% with piperonyl butoxide 4% (synergized pyrethrin, Rid, Pronto), unless there is a documented resistance problem in the neighborhood.
Apply for ten minutes, then rinse.
Apply synergized pyrethrin again after 7 to 10 days (day 9 is ideal); permethrin may also be required if live lice are found.
Application-site erythema, ocular erythema, and application-site irritation are side effects.
Body lice are best treated with a single application of synergized pyrethrin lotion that is kept on for several hours.
For 10 days, apply petroleum jelly BID to eyelash fungus.
Precautions: Pyrethrin should be avoided by people who have ragweed allergies since it may cause respiratory problems.
- Eyelash infections should never be treated with pediculicides.
Lice on the head and pubic lice
Apply for 8 to 12 hours, then wash off Malathion 0.5% lotion (Ovide).
Its effectiveness may be aided by the excipients terpineol (12%) and isopropyl alcohol (78%):
Despite ovicidal efficacy, a second application may be required after 7 to 10 days (day 9 is ideal), if live lice are seen. They are also flammable and have a foul smell.
1% Lindane shampoo is no longer advised
Apply for 4 minutes, then wash (don't do this again).
Aplastic anemia and neurotoxicity (seizures, muscular spasms) are side effects.
Uncontrolled seizure disorder and premature newborns are contraindicated.
Use with caution if you have excoriated skin, are immunocompromised, have a medical condition that puts you at risk for seizures, or are taking drugs that lower your seizure threshold.
Possible interactions include using drugs that reduce the seizure threshold while using this product.
Apply Spinosad 0.9% lotion (Natroba) on dry hair and scalp for 10 minutes, then rinse with warm water to get rid of head lice. Observe again in 7 days if live lice are found.
Benzyl alcohol 5% lotion (Ulesfia) side effects include erythema at the application site, eye redness, and irritation.
Apply to dry hair, moistening the scalp and hair as needed (amount will depend on length of hair), rinse after 10 minutes, and repeat once a week.
Application side effects include pruritus, erythema, pyoderma, and eye discomfort.Apply Ivermectin 0.5% lotion (Sklice) to dry hair, saturating the scalp and hair with up to 4 ounces, and rinse after 10 minutes to relieve site irritation.
Burning at the application site, dandruff, dry skin, and eye discomfort are some of the side effects.
 Mechanical lice and nit removal, which involves thoroughly soaking hair and combing it with a fine-toothed comb every three to four days for two weeks to get rid of all lice as they hatch.


Caution 
Use lindane only if first-line treatments have failed due to FDA black box warning of serious brain damage. The National Pediculosis Association outright discourages the use of lindane.
Child Safety Considerations
Avoid using permethrin and synergized pyrethrin on babies under two months old. Avoid malathion in children under the age of two and benzyl alcohol, topical ivermectin, and spinosad in children under the age of six months.
Lindane is not advised.
pregnant women's issues
Pregnancy Category B substances include permethrin, synergized pyrethrin, malathion, spinosad, and benzyl alcohol. Topical ivermectin and lindane fall under pregnancy Category C.

Further Therapies 
Topical 0.5% malathion lotion is not as effective for "difficult to treat" instances of head lice as oral ivermectin 400 g/kg, given twice at a 7-day interval.
Ivermectin: pregnancy Category C; 200 g/kg PO repeated after 10 days or 300 g/kg PO repeated after 7 days; should not be used in children under 15 kg; not FDA-approved for lice
 Only use oral trimethoprim/sulfamethoxazole (TMP/SMX), which is not FDA-approved for treating lice, in combination with permethrin 1% in situations of repeated treatment failures or probable resistance to medication.
The FDA has not approved permethrin 5% cream (Rx) for treating lice, and it is unlikely that it will work on lice that are resistant to 1% cream rinse.

Healthcare Alternatives 

Apply thoroughly to hair, comb through, and dry with a hair dryer before shampooing after eight hours. Cetaphil lotion is a dry-on, suffocation-based pediculicide (not FDA-approved for lice).
- Repeat three times in all, once every week until the condition is resolved.
Dimethicone 4% lotion (not FDA-approved for lice treatment): Apply to hair for 8 hours; reapply after a week.
There is no evidence to support the effectiveness of household treatments such vinegar, isopropyl alcohol, olive oil, ylang ylang oil, mayonnaise, melted butter, and petroleum jelly.
Clinical trials have not been conducted to test herbal shampoos and pomades.
Tea tree oil and lavender oil should not be used to treat lice since they have been linked to the development of prepubertal gynecomastia in males.
Electronic louse combs haven't worked well, and the FDA hasn't approved them either.

Take Action 

After receiving topical therapy, kids can go back to school even if there are still nits present. No-nit rules are superfluous.
patient observation
If there aren't any dead lice present 8 to 12 hours following treatment, drug resistance should be considered.

Prognosis: >90% cure rate with appropriate therapy; frequent recurrence, mostly due to reinfection or non-adherence to treatment. Synthetic pyrethroid resistance is rising.

Complications include persistent itching brought on by overuse of the pediculicide and poor sleep caused by pruritus.
Secondary bacterial illnesses; social stigma; missed school; body lice can spread typhus and trench fever

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