Papular pruritic eruption of Demodex folliculitis in patients with acquired immunodeficiency syndrome

Demodicosis in Different Age Groups and Alternative Treatment Options-A Review

Infestation with Demodex mites is a common occurrence, especially in adults and the elderly. More recent attention has been paid to the presence of Demodex spp. mites in children, even ones without comorbidities. It causes both dermatological and ophthalmological problems. The presence of Demodex spp. is often asymptomatic, thus it is suggested to include parasitological investigation tests in dermatological diagnostics, in addition to bacteriological analysis. Literature reports show that Demodex spp. are related to the pathogenesis of numerous dermatoses, including rosacea or demodicosis gravis, and common eye pathologies reported by patients such as dry eye syndrome or ocular surface inflammatory conditions, such as blepharitis, chalazia, Meibomian gland dysfunction, and keratitis. Treatment of patients is a challenge and is usually prolonged, therefore it is important to carefully diagnose and properly select the therapy regimen for the treatment to be successful, and with minimal side effects, especially for young patients. Apart from the use of essential oils, research is ongoing for new alternative preparations active against Demodex sp. Our review was focused on the analysis of the current literature data on the available agents in the treatment of demodicosis in adults and children.

The Pathogenic Role of Demodex Mites in Rosacea: A Potential Therapeutic Target Already in Erythematotelangiectatic Rosacea?

Rosacea is a common facial dermatosis but its definition and classification are still unclear, especially in terms of its links with demodicosis. Triggers of rosacea (ultraviolet light, heat, spicy foods, alcohol, stress, microbes) are currently considered to induce a cascading innate and then adaptive immune response that gets out of control. Recent histological and biochemical studies support the concept that this inflammatory response is a continuum, already present from the onset of the disease, even when no clinical signs of inflammation are visible. The Demodex mite is beginning to be accepted as one of the triggers of this inflammatory cascade, and its proliferation as a marker of rosacea; moreover, the papulopustules of rosacea can be effectively treated with topical acaricidal agents. Demodex proliferation appears to be a continuum process in rosacea, and may not be clinically visible at the onset of the disease. Molecular studies suggest that Demodex may induce tolerogenic dendritic cells and collaborate with vascular endothelial growth factor (VEGF) to induce T cell exhaustion and favor its own proliferation. These interactions among VEGF, Demodex, and immunity need to be explored further and the nosology of rosacea adapted accordingly. However, treating early rosacea, with only clinically visible vascular symptoms, with an acaricide may decrease early inflammation, limit potential flare-ups following laser treatment, and prevent the ultimate development of the papulopustules of rosacea. The effectiveness of this approach needs to be confirmed by prospective controlled clinical trials with long-term follow-up. Currently, the evidence suggests that patients with only vascular symptoms of rosacea should be carefully examined for the presence of follicular scales as signs of Demodex overgrowth or pityriasis folliculorum so that these patients, at least, can be treated early with an acaricidal cream.

Comparison of the efficacy of tea tree (Melaleuca alternifolia) oil with other current pharmacological management in human demodicosis: A Systematic Review

Various treatments are found to be moderately effective in managing Demodex-related diseases except tea tree oil (TTO) and terpinen-4-ol (T4O), which showed superior miticidal and anti-inflammatory effects in numerous clinical studies. Their possible effects include lowering mite counts, relieving Demodex-related symptoms, and modulating the immune system. This review summarizes the current clinical topical and oral treatments in human demodicosis, their possible mechanisms of action, side-effects and resistance in treating this condition. TTO (especially T4O) is found to be the most effective followed by metronidazole, ivermectin and permethrin in managing the disease. This is because TTO has anti-parasitic, anti-bacterial, anti-fungal, anti-inflammatory and wound-healing effects. Furthermore, nanoTTO can even release its contents into fungus and Pseudomonas biofilms. Combinations of different treatments are occasionally needed for refractory cases, especially for individuals with underlying genetic predisposal or are immuno-compromised. Although the current treatments show efficacy in controlling the Demodex mite population and the related symptoms, further research needs to be focused on the efficacy and drug delivery technology in order to develop alternative treatments with better side-effects profiles, less toxicity, lower risk of resistance and are more cost-effective.

Ocular Demodicosis as a Potential Cause of Ocular Surface Inflammation

Among different species of mites, Demodex folliculorum and Demodex brevis are the only 2 that affect the human eye. Because demodicosis is highly age-dependent and can be found in asymptomatic adults, the pathogenicity of these mites has long been debated. In this study, we summarize our research experience including our most recent study regarding Demodex infestation as a potential cause of ocular inflammatory diseases. Specifically, we describe the pathogenesis of demodicosis and then discuss the results of work investigating the associations and relationships between ocular demodicosis and blepharitis, meibomian gland diseases, and keratitis, in turn. This is followed by some discussion of the diagnosis of demodicosis and concludes with a brief discussion of evidence for different treatments for ocular demodicosis. Collectively, our studies suggest a strong correlation between ocular demodicosis and ocular surface inflammatory conditions, such as blepharitis, chalazia, meibomian gland dysfunction, and keratitis. Further investigation of the underlying pathogenic mechanism is warranted.

[Cutaneous infections: Pathologist's role in unusual or atypical situations]

In infectious pathology, the gold standard consists of the detection of the pathogen within the sample. Identification of the pathogen is often difficult despite the presence of few and inexpensive tools, such, as special stain, immunohistochemistry, or in situ hybridization specific of the pathogen. In infectious pathology, there are morphological signs, which can guide us towards an etiology. We present some clinicopathological examples illustrating rare or unusual situations in cutaneous infectious pathology.

The efficacy of tea tree face wash, 1, 2-Octanediol and microblepharoexfoliation in treating Demodex folliculorum blepharitis

PURPOSE

To compare the efficacy of Dr Organic Tea Tree Face Wash, OcuSoft Lids Scrub Plus and the BlephEx™ device at treating of Demodex folliculorum blepharitis.

METHODS

Eighty-six subjects (33 males/36 females) were enrolled in a randomised controlled interventional treatment study. Subjects completed a dry eye symptom questionnaire and were assessed for presence of Demodex folliculorum. Subjects were divided into three groups according to treatment: Dr Organic Tea Tree Face Wash (A) (n=28), OcuSoft Lid Scrub Plus (B) (n=30), or in-house lid scrub with the BlephEx™ device before nightly lid scrubs with OcuSoft Lid Scrub Plus (C) (n=28). Subjects were advised to clean their eyelids nightly for four weeks. Each subject was re-assessed for symptoms and Demodex folliculorum blepharitis after two weeks and four weeks of treatment.

RESULTS

The quantity of Demodex folliculorum was significantly reduced after four weeks of treatment in all three groups (p<0.05). Overall, there was no difference in efficacy between the three treatments (p>0.1). Symptoms reported by subjects were significantly improved after two and four weeks of treatment (p<0.05). Overall, there was no difference in efficacy between the three treatments to reduce symptoms after two or four weeks (p= 0.813 and p=0.646 respectively).

CONCLUSION

All three methods tested have shown good ability to reduce Demodex folliculorum quantity, improve subjective symptoms and help treat Demodex folliculorum blepharitis.

High prevalence of demodex brevis infestation in chalazia

PURPOSE

To investigate the correlation between demodicosis and chalazia in patients with the latter.

DESIGN

Prospective, observational, comparative study.

METHODS

Forty-four adult and 47 pediatric patients with chalazia and 34 adult and 30 pediatric age- and sex-matched patients without chalazia treated at an institutional referral eye center were included. All 155 patients underwent lash sampling followed by microscopic identification and counting of Demodex mites. All 91 patients with chalazia underwent surgical removal, and among them, 74 were followed up for 18 ± 4.3 months after surgery. Statistical correlation between ocular demodicosis and chalazia and its postoperative recurrence was performed.

RESULTS

Demodicosis was significantly more prevalent in chalazia patients than in control patients as a group (69.2% vs 20.3%) and when separated into pediatric (70.2% vs 13.3%) and adult (68.2% vs 26.5%) subgroups (all P < .001). Demodicosis was associated strongly with chalazia (odds ratio, 4.39; 95% confidence interval, 2.17 to 8.87; P < .001). D. brevis was significantly more prevalent (odds ratio, 18.21; 95% confidence interval, 2.22 to 149.74; P = .01) than D. folliculorum (odds ratio, 2.82; 95% confidence interval, 1.16 to 6.84, P = .02) in patients with chalazia. Patients with demodicosis tended to demonstrate recurrence (33.3% vs 10.3%; P = .02), especially in those with D. brevis (35.1% vs 13.5%; P = .03).

CONCLUSIONS

There is a high prevalence of demodicosis, especially cases of caused by D. brevis, in adult and pediatric patients with chalazia, suggesting that ocular demodicosis is a risk factor for chalazia.

Evaluation of the efficacy of oral ivermectin in comparison with ivermectin-metronidazole combined therapy in the treatment of ocular and skin lesions of Demodex folliculorum

OBJECTIVE

To evaluate the efficacy of ivermectin and combined ivermectin-metronidazole therapy in the treatment of ocular and skin lesions of Demodex folliculorum.

METHODS

One hundred twenty patients with skin lesions and anterior blepharitis, whose infestation was treatment-resistant and who had a Demodex count >5 mites/cm² for skin lesions or ≥ 3 mites at the root of each eyelash, were recruited. The treatment regimens were ivermectin and ivermectin-metronidazole combined therapy. We enrolled 15 patients from each of four groups for each treatment regimen. Demodex was detected by standardized skin surface biopsy for skin lesions. Three eyelashes from each affected lower eyelid were epilated and examined. The study subjects were followed-up once a week for four visits.

RESULTS

There was a difference in the mite count between the subgroups taking ivermectin and combined therapy during all follow-up visits. At the last visit, in the combined therapy subgroup, 1.7% of patients showed no clinical improvement, 26.7% showed a marked clinical improvement, and 71.6% showed complete remission. In those on the ivermectin regimen, 27 patients had a mite count >5 mites/cm², 21.7% showed no clinical improvement, 33.3% showed a marked improvement, and 45% showed complete remission.

CONCLUSIONS

Combined therapy was superior in decreasing the D. folliculorum count in all groups and in reducing the mite count to the normal level in rosacea and in anterior blepharitis. On the other hand, the two regimens were comparable in reducing the mite count to the normal level in acne and peri-oral dermatitis lesions.

Ocular demodicosis as a potential cause of pediatric blepharoconjunctivitis

PURPOSE

To report Demodex infestation in pediatric blepharoconjunctivitis.

METHODS

A retrospective review of 12 patients, with ages from 2.5-11 years, with chronic blepharoconjunctivitis who failed to respond to conventional treatments. Demodex was detected by lash sampling and microscopic examination. Patients were treated with 50% tea tree oil (TTO) eyelid scrubs or 5% TTO ointment eyelid massages for 4-6 weeks.

RESULTS

Demodex mites were found in all, but 1 case had cylindrical dandruff in the lashes. After 1 week of TTO treatment, all patients showed dramatic resolution of ocular irritation and inflammation while Demodex counts dropped. All corneal signs resolved within 2 weeks except for a residual anterior stromal scar in 1 eye. During a follow-up period of 8.3 ± 4.6 months, 1 patient showed recurrent inflammation, which was successfully managed by a second round of TTO treatment.

CONCLUSIONS

Demodicosis should be considered as a potential cause of pediatric refractory blepharoconjunctivitis. Eyelid scrubs or massage with TTO could be an effective treatment regimen in these cases.

Dermatologic Immune Restoration Syndrome: Report of Five Cases from a Tertiary Care Center in North India

Background:

Dermatologic conditions are often an early clue to human immunodeficiency virus (HIV) infection. As the disease progresses and the host immunity fails, patients may develop a number of skin conditions. At this point, they have a dominant T helper 2 immunologic response. After the initiation of antiretroviral therapy, the T helper 1 response is restored, and some skin problems, paradoxically, make their appearance then.

Conclusion:

Herpes zoster, mucocutaneous herpes, eosinophilic folliculitis, and mycobacterial infections have been known to occur at this stage. This may be because immune restoration of a host's immunity causes recognition of silent or latent infection and results in development of the condition. We report five cases that were seen at our center during a 2-year period.

Comparison of Demodex folliculorum density in haemodialysis patients with a control group

BACKGROUND

Demodex folliculorum (DF) is resident in human pilosebaceous follicles. Mite density is low in healthy skin. Many cases of demodicosis in association with immunosuppression have been reported. Patients undergoing haemodialysis are also immunosuppressed.

OBJECTIVE

We aimed to compare the Demodex folliculorum density in haemodialysis patients and healthy subjects.

METHODS

Mite density of 87 patients undergoing haemodialysis was compared with that of age- and sex-matched controls. Two samples of standardized skin surface biopsies were taken from each subject from the forehead, cheek and nose. The number of mites counted on the surface area of 1 cm2 was accepted as the density of DF. The length and width of mites were measured by oculometer.

RESULTS

DF density was found in 17 (19.54%) of the 87 dialysis patients and in 9 (10.34%) of 87 controls. A mean mite density of 5.11+/-5.65 was found in dialysis patients and of 2.55+/-1.6 in controls. Differences between the two groups in mite density were not statistically significant (P=0.13). There was also no significant difference in mite length between the two groups (P=0.06). There was, however, a significant difference in mite width (P=0.018).

CONCLUSION

Despite the presence of sebaceous gland atrophy in haemodialysis patients, the higher density of DF in these patients than controls supports the supposition that this mite can increase immunosuppression.

Pruritic Papular Eruption in HIV

Pruritic papular eruption (PPE) is characterized chronic pruritus and symmetric papular eruptions on the trunk and extremities with the absence of other definable causes of itching in an HIV-infected patient. PPE seems to be much more prevalent in less developed regions of the world. The etiology of this distressing condition is unclear, although an inappropriate response to an exogenous agent, such as arthropod bites, may underlie the pathogenesis. Identifying PPE's association with the immune dysregulation of HIV and distinguishing this condition from other pruritic disorders found in HIV-infected patients is important for optimal management.

Ivermectin treatment of three cases of demodecidosis during human immunodeficiency virus infection

Demodecidosis is an ectoparasitosis that is infrequently observed in subjects with human immunodeficiency virus (HIV) infection. It has a rosacea-like presentation. We present three cases in patients with acquired immunodeficiency syndrome (AIDS). Two of these patients had a profuse eruption, and all three cases were cured by ivermectin. The single-dose treatment could be repeated in cases of subsequent recurrence. Ivermectin thus seems to be a good alternative in the treatment of demodecidosis in patients with HIV infection.

Environmental scanning electron microscopy observation of the ultrastructure of Demodex

In this study, numbers of Demodex of hair follicles and sebaceous glands were prepared and the ultrastructure (especially the mouthparts) of Demodex was observed firstly with environmental scanning electron microscopy (ESEM). The most suitable treatment methods and optimal environmental condition for observing the genus samples were found. The samples were washed with detergent and rinsed with distilled water, and then were taken to the specimen stage, on which there was carbon adhesive tape, using special tools. When the temperature was at 5 degrees C and chamber pressure at 5 mbar respectively, the surface of the samples could be fully imaged without covering water or dehydration. The sample surfaces were plump and clear without postmortem changes and charging artifacts. Detailed information about each part of Demodex was observed by ESEM, and clear three-dimensional images were recorded. The mouthparts of D. folliculorum were composed of a complex set of structures, which included a round oral opening, a sharp oral needle, and a special hypostome that looked like a longitudinal spindle in the central position. On the end segment of palpus, there were seven strong palpal claws located on each side of the mouthparts. D. folliculorum had special piercing mouthparts, while the mouthparts of D. brevis were a simpler structure. We could not observe the oral needle of D. brevis, and there were only five pairs of palpal claws on the end segment of palpus. The offensive organs of Demodex resulted in its pathogenic effects. After studying hundreds of Demodex, we identified both female and male species of D. folliculorum, but only females of D. brevis in our sample.

Refractory Demodex folliculitis in five children with acute lymphoblastic leukemia

We report five children with acute lymphocytic leukemia on maintenance chemotherapy who had Demodex folliculitis. None experienced complete clearing when treated with permethrin 5% cream. Topical metronidazole helped to lessen the eruption in four, but did not provide full clearing. The one child who was treated with sodium sulfacetamide 10%, sulfur 5% formulation had resolution of the eruption. We suggest that treatment of Demodex folliculitis in children with acute lymphocytic leukemia is more difficult than is suggested in the literature. Newer sodium sulfacetamide/sulfur formulations should be considered when treating this condition, particularly in children with acute lymphocytic leukemia.

Démodécie chez un malade infecté par le VIH : guérison par ivermectine

INTRODUCTION

Demodex is a saprophyte parasite in mammals. In Man, it is associated with differing clinical profiles (rosacea-like dermatitis, folliculitis and blepharitis). We report a case of demodecidosis in an HIV-infected patient that was successfully treated with ivermectin.

CASE REPORT

A man from Laos, infected by HIV and treated for glandular tuberculosis, presented with a prurigenous eruption on the face and the pre-sternal and interscapular areas. Direct examination of scraped product and histopathological examinations confirmed the diagnosis of demodecidosis. Clinical cure was obtained after 2 single cures of ivermectin a one month's distance.

DISCUSSION

The features of demodecidosis are often similar to those of rosacea. In immunodeficient patients, the semiology remains the same but the eruption is more abundant. During HIV-infection, demodecidosis occurs at the AIDS stage or with a CD4 count lower than 200/mm3. Many anti-dust mite molecules are used to treat the disease but frequently lead to irritation. Administration of a single cure of ivermectin, repeated if necessary, appears to be an interesting alternative to contact anti-dust mite agents.

Folliculitis: recognition and management

Folliculitis is an inflammatory reaction in the superficial aspect of the hair follicle and can involve the follicular opening or the perifollicular hair follicles. The pilosebaceous unit of the follicle is divided into three compartments: the infundibulum (superficial part, outlined by the sebaceous duct), the isthmus (between the sebaceous duct and arrector pili protuberance), and the inferior segment (stem and hair bulb). This anatomical scheme forms the basis for any evaluation of the clinical manifestations of folliculitis. Most of the follicular conditions can be classified according to their anatomical location and histopathologic patterns. Clinically, the inflammation manifests as 1mm-wide vesicles, pustules, or papulopustules in acute cases; however, hyperkeratosis and keratotic plug formations are indicative of a chronic process. The presence of superficial pustules does not always imply an infectious origin, as there are many noninfectious types of folliculitis. In this review, we describe the different types of folliculitis based on their etiology, clinical manifestation, and treatment. We also discuss some newly described disorders and the latest information on their treatment.

Demodex abscesses: clinical and therapeutic challenges

A 53-year-old man had a 6-week history of confluent erythematous papules, pustules, and abscesses of the face initially limited to the right nasolabial fold. Histologic investigation revealed a perifollicular infiltrate with lymphocytes, histiocytes, and many Demodex folliculorum mites. A large number of mites were seen in skin scrapings. The skin manifestations progressed and persisted for the following 5 years and were unresponsive to numerous antiparasitic treatments, including repeated oral administration of ivermectin and external application of lindane, permethrin, and benzoyl benzoate. Therapy with oral administration of 250 mg metronidazole 3 times a day for 2 weeks resulted in rapid and lasting recovery. Demodex folliculitis remains a diagnostic and therapeutic challenge. Antiparasitic therapies used against lice or scabies may fail in control of D folliculorum mites. In the presence of clinical and microscopic findings typical of Demodex folliculitis or abscesses, treatment failure with acaricidal agents does not exclude the diagnosis. Oral metronidazole seems to work in the management of this chronic mite infestation.

Rosacea-like demodicidosis in an immunocompromised child

Demodex folliculorum is a saprophytic mite of the human pilosebaceous unit. It is rarely found in children. It has been implicated in the development of follicular pityriasis, rosacea-like demodicidosis, pustular folliculitis, blepharitis, and granulomatous rosacea. We describe a 4-year-old boy who developed asymptomatic facial lesions that histologically corresponded to demodicidosis. He was in clinical remission of acute lymphoblastic leukemia and currently receiving maintenance chemotherapy. Exanthems related to D. folliculorum are rare in children. Most cases occur in immunocompromised patients and the clinical and histologic findings are diverse. A differential diagnosis should be established with rosacea and perioral dermatitis. The role of Demodex in the pathogenesis of these disorders is controversial. Immunosuppression might increase the number of mites, favoring an inflammatory reaction, or there could exist an impaired cutaneous immunologic response to the parasites.

Rosacea-like demodicidosis associated with acquired immunodeficiency syndrome

We present a 35-year-old patient with acquired immunodeficiency syndrome who had demodicidosis on his face, characterized by multiple papules and papulopustules, associated pruritus, numerous mites on skin-surface biopsy and in biopsy specimens, and rapid response to topical treatment with permethrin. It seems likely that Demodex infestation does not manifest unless local or systemic immune function is altered, leading to the proliferation of the organism and subsequent disease.

Demodex folliculorum in pregnancy

BACKGROUND

Demodex folliculorum (DF), which is a resident in human pilosebaceous follicles, has been implicated in rosacea, blepharitis, pityriasis folliculorum, pustular folliculitis, and skin lesions of immunosuppressed patients on chemotherapy or with acquired immunodeficiency syndrome (AIDS).

OBJECTIVE

We aimed to determine the influence of pregnancy on the carriage of DF.

METHODS

Mite density in 40 pregnant women was compared with that of age- and sex-matched controls. Two standardized skin surface biopsies were taken from each subject. Results In pregnant women, DF was found at 0.55/cm2, compared with a mean value of 1.2/ cm2 in nonpregnant controls. The difference between the two groups was not statistically significant (Mann-Whitney test, P = 0.22).

CONCLUSIONS

Our findings indicate that pregnancy may not have a direct effect on mite density.

Distinct serum cytokines in AIDS-related skin diseases

To determine whether common skin diseases associated with human immunodeficiency virus (HIV) were distinguishable based on the pattern of serum cytokine expression, we studied patients with psoriasis, pruritus, and Kaposi's sarcoma (KS) for levels of tumor necrosis factor (TNF)-alpha, interferon-gamma (IFN-y), interleukin (IL)-10, and IL-4. Thirty-two HIV-positive (HIV+) patients including 8 with KS, 11 with psoriasis, and 13 with pruritus along with 16 HIV-negative subjects with psoriasis were studied. IFN-gamma levels were highest in sera of HIV+ patients with psoriasis (p = 0.040). By contrast, TNF-alpha and IL-10 levels were highest in sera of HIV+ patients with pruritus (p = 0.012). Detectable levels of all cytokines in these patients were remarkably higher than for healthy adults. These results suggest that common skin diseases associated with HIV infection and AIDS can be distinguished by the production of unique cytokines.

HIV-related eosinophilic folliculitis: a panel discussion

Eosinophilic folliculitis is a common cause of morbidity in patients infected with the human immunodeficiency virus (HIV) and a marker of the acquired immunodeficiency syndrome (AIDS). No causative organism has yet been identified, although an aberrant Th2-type immune response to a follicular antigen appears relevant to pathogenesis. A variety of treatments have been reported to minimize the inflammatory component, relieve the concomitant pruritus, and/or favorably alter the cutaneous microenvironment.

Demodicidosis in an immunodeficient child

A 15-month-old girl developed acute lymphoblastic leukemia. Chemotherapy had induced a complete remission and she was continued on maintenance therapy. At 3 years of age, she developed an eruption consisting of excoriated papules and pustules on the face. Demodex folliculorum seemed to be the cause. Topical treatment with metronidazole applied twice a day over a period of 2 weeks resulted in partial improvement. The dermatosis finally cleared gradually with oral erythromycin therapy and one overnight application of 1% lindane cream per week for 2 successive weeks.

Demodicidosis or rosacea: what did we treat?

We report a 75-year-old man with a fulminant rosacea-like eruption, suggestive of demodicidosis. Multiple Demodex folliculorum mites were found in facial scales and pustules and, on histological examination, in the infundibulum of pilosebaceous follicles and in the dermis. Intradermal mites were surrounded either by polymorphonuclear granulocytes and histiocytes, or by a granulomatous infiltrate containing foreign-body giant cells, which had phagocytosed the parasites. Complete recovery, with disappearance of facial mites, was achieved by treatment with a combination of oral and topical metronidazole, although this drug is not known to be miticidal.

Human immunodeficiency virus and the skin: selected controversies

Acquired immunodeficiency syndrome was first recognized as a new disease in 1981 because of the unusual association of Kaposi's sarcoma and Pneumocystis carinii pneumonia in young men. The skin remains one of the most important clinical markers for acquired immunodeficiency syndrome, now recognized as the end stage of infection with the human immunodeficiency virus (HIV). Indeed, an urticarial viral exanthem appearing during seroconversion may allow early identification of newly infected individuals who might benefit from administration of antiviral therapy during plasma viremia. The "asymptomatic HIV infection" is often accompanied by multiple skin complaints, which commonly include xerosis, pruritus, psoriasis/seborrheic dermatitis, and pruritic papular eruptions, the cause of which remains controversial. Psoriasis and Kaposi's sarcoma lesions share features including angiogenesis, dermal dendrocytes infected with HIV, and epidermal hyperproliferation, and are manifested by mice transgenic for HIV provirus or Tat-ltr. Changes in the immune system including T-cell function, antigen response, and shifting cytokine expression as well as a propensity for autoimmune reactions must underlie the skin immunodysfunction occurring in the setting of HIV infection. One of the most unsettling controversies suggested by in vitro data is that ultraviolet light, an effective therapy for HIV-related skin disorders, may actually activate the virus.

Demodicidosis in a child with leukemia

A 2-year-old girl developed acute lymphoblastic leukemia at the age of 9 months. She was treated successfully with chemotherapy but developed a pruritic, papulopustular facial eruption that was caused by Demodex folliculorum. The eruption cleared after treatment with one overnight application of 5% permethrin cream. Demodicidosis should be included in the differential diagnosis of facial eruptions in children who undergo chemotherapy and in those with congenital or acquired immunodeficiency.