B85.4 Mixed pediculosis and phthiriasis

Name of the Condition

• Mixed pediculosis and phthiriasis

Summary

Mixed pediculosis and phthiriasis is a parasitic infestation involving multiple types of lice, including head lice (Pediculus humanus capitis), body lice (Pediculus humanus corporis), and pubic lice (Phthirus pubis). This condition occurs when an individual is infested with more than one species of lice simultaneously. It is highly contagious and spreads through direct contact or shared personal items. Infestations typically present with itching and visible lice or nits (lice eggs) on the affected areas.

Causes

The infestation is caused by a combination of lice species: head lice, body lice, and pubic lice. Transmission occurs through close personal contact, sharing of combs, hats, clothing, or bedding, or sexual contact (for pubic lice). Lice cannot jump or fly but crawl between hosts. Body lice are often associated with poor hygiene or crowded living conditions, while head and pubic lice can affect anyone regardless of cleanliness.

Risk Factors

• Close contact with an infested individual, such as in households, schools, or daycare settings.
• Sharing personal items like combs, brushes, hats, or bedding.
• Sexual activity, which increases the risk of pubic lice transmission.
• Crowded living conditions or infrequent washing of clothing and bedding.

Symptoms

• Intense itching in affected areas (scalp, body, or pubic region).
• Visible lice or nits on hair, skin, or clothing.
• Skin irritation or secondary infections from scratching.

Diagnosis

Diagnosis is confirmed by visual inspection of the affected areas for lice or nits. Healthcare providers may use a magnifying glass or comb to identify the parasites. A thorough examination of the scalp, body, and pubic region is necessary to detect multiple infestations. No laboratory tests are typically required.

Treatment Options

Treatment involves topical or oral medications to eliminate lice, such as permethrin, ivermectin, or malathion. All clothing, bedding, and personal items must be washed in hot water and dried on high heat to kill lice and nits. Close contacts should be examined and treated if infested. Repeat treatment may be necessary to ensure all lice are eradicated.

Prognosis and Follow-Up

With proper treatment, the prognosis is excellent, and infestations resolve within 1–2 weeks. Follow-up is recommended to confirm eradication and check for reinfestation. Itching may persist for a few days after treatment due to allergic reactions to lice bites.

Complications

• Secondary bacterial infections from scratching.
• Skin irritation or allergic reactions to lice bites.
• Social or psychological distress due to the infestation.

Lifestyle & Prevention

• Avoid sharing personal items like combs, hats, or clothing.
• Maintain good hygiene, including regular washing of clothing and bedding.
• Conduct regular head checks in high-risk settings (schools, daycare).
• Treat all close contacts simultaneously to prevent reinfestation.

When to Seek Professional Help

Seek medical attention if itching is severe, if there are signs of infection (e.g., pus, swelling), or if over-the-counter treatments fail. Infestations in infants, pregnant individuals, or those with open wounds require prompt evaluation.

Tips for Medical Coders

Document the presence of multiple lice species (head, body, pubic) to support the diagnosis of mixed pediculosis and phthiriasis. Include details on affected areas and transmission routes. Ensure coding aligns with clinical findings and avoids overlapping with single-species infestations.