Depletion of cutaneous peptidergic innervation in HIV-associated xerosis

[Skin symptoms associated with human immunodeficiency virus infection]

The recently observed accelerated increase of human immunodeficiency virus infection in Hungary poses a major public concern for the healthcare system. Given the effective only but not the curative therapy, prevention should be emphasized. Current statistics estimate that about 50% of the infected persons are not aware of their human immunodeficiency virus-positivity. Thus, early diagnosis of the infection by serological screening and timely recognition of the disease-associated symptoms are crucial. The authors' intention is to facilitate early infection detection with this review on human immunodeficiency virus-associated skin symptoms, and highlight the significance of human immunodeficiency virus care in the everyday medical practice.

Long-Term Effect of Acetyl-L-Carnitine for Antiretroviral Toxic Neuropathy

BACKGROUND

Nucleoside analogue reverse transcriptase inhibitors (NRTIs) used for the treatment of HIV can a cause distal symmetrical peripheral polyneuropathy by disruption of mitochondrial metabolism. Treatment with acetyl-L-carnitine (ALCAR) has shown short-term symptomatic and histological improvement. Long-term effects have not been investigated.

PURPOSE

To assess the subjective and objective degree of antiretroviral toxic neuropathy (ATN) during treatment with ALCAR.

METHOD

A cohort of 21 patients with ATN who commenced treatment with ALCAR between March 1999 and October 2001 was reviewed after a mean of 4.3 years using standardized questionnaires and neurological examination.

RESULTS

Of the 21 patients, 2 had died and 3 were lost to follow-up. 16 patients were assessed. 10 were still on potentially neurotoxic drugs. 13 were still taking ALCAR. 9 were pain free. The most common symptom was numbness (mild, moderate, and severe in 12, 3, and 0 patients, respectively), followed by paraesthesia (8, 2, 2), pain (4, 3, 0), and burning (5, 2, 0). There was mildly reduced sensation in the toes of 8 patients. 13 patients reported that ALCAR had improved their symptoms very much or moderately, 2 reported no change, and 1 reported a moderate worsening.

CONCLUSION

ALCAR led to long-term symptomatic improvement in most patients without the need to discontinue neurotoxic drugs. Although in this study there was no control group, this agent appears to be an effective pathogenesis-based treatment for ATN.

New insights into HIV-1-primary skin disorders

Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis.

Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4⁺ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation.

The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations.

Prevalence and factors associated with dry skin in HIV infection: the FRAM study

OBJECTIVE

Complaints of dry skin in HIV-infected individuals were reported after the advent of HAART. The objective of the study was to evaluate the prevalence of dry skin and associated factors in HIV-infected and control subjects.

DESIGN

Cross-sectional.

METHODS

A total of 1026 HIV-infected subjects and 274 controls [from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a population-based study of cardiovascular risk assessment] in the Study of Fat Redistribution and Metabolic Change in HIV infection (FRAM) had skin assessed by self-report and examination. Multivariable logistic regression identified factors associated with dry skin.

RESULTS

Self-reported dry skin was more prevalent in HIV-infected subjects than controls. In multivariable analysis, HIV infection was associated with self-reported dry skin. In HIV-infected men, current indinavir use, CD4 cell count less than 200 cells/microl and recent opportunistic infections were associated with dry skin. Indinavir use had an elevated risk in men with CD4 cell counts of 200 cells/microl or greater but not with CD4 cell counts less than 200 cells/microl. In HIV-infected women, a CD4 cell count less than 200 cells/microl was associated with dry skin; indinavir use did not reach statistical significance but, as in men, indinavir use had an elevated risk in those with higher CD4 cell counts than in those with CD4 cell counts less than cells/microl.

CONCLUSION

Dry skin is more common in HIV-infected individuals than controls. In HIV-infected individuals, low CD4 cell counts and indinavir use in those with higher CD4 cell counts are associated with dry skin.

Re-organization of P2X3 receptor localization on epidermal nerve fibers in a murine model of cancer pain

To determine whether ATP and P2X3 receptors contribute to bone-cancer pain in a mouse model, immunohistochemical techniques were used to identify whether changes in the labeling of P2X3 receptors on epidermal nerve fibers (ENFs) occurred during tumor development. C3H mice were injected with osteolytic fibrosarcoma cells in and around the calcaneus bone. These mice exhibited mechanical hyperalgesia by day 10 post-implantation as assessed using von Frey monofilaments. Biopsies of the plantar skin overlying the tumor were obtained at days 10, 14, and 18 post-implantation. Confocal images were analyzed for the number of PGP 9.5, P2X3, and CGRP immunoreactive (ir) ENFs. The overall ENF population (PGP-ir) decreased progressively over time, whereas the subsets of P2X3-ir fibers demonstrated a modest increase and CGRP-ir nerve fibers remained fairly constant. Importantly, the proportion of CGRP-ir fibers that labeled for P2X3 increased from approximately 6% in control animals to nearly 30% at day 14 following tumor cell implantation. These studies demonstrate increased expression of P2X3 receptors on CGRP-ir ENFs during tumor growth and suggest a role for ATP in cancer-related pain.

Xerosis and pruritus in the elderly: recognition and management

Xerosis (dry skin) is characterized by pruritic, dry, cracked and fissured skin. Dry skin may be diagnosed as xerosis, eczema craquelé, dyshidrotic eczema, or asteatotic eczema. Two of the most common dermatologic problems found in nursing home residents are xerosis and pruitus. This article focuses on the recognition and treatment of these conditions, and stresses the importance of comprehensive treatment for these conditions as a preventative against stasis dermatitis and ulcer formation.

Histopathological and immunohistochemical assessment of acquired ichthyosis in patients with human T-cell lymphotropic virus type I-associated myelopathy

BACKGROUND

Patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy frequently display cutaneous alterations such as acquired ichthyosis.

OBJECTIVES

Elucidation of the pattern of acquired ichthyosis in HTLV-I-associated myelopathy.

METHODS

Skin fragments from 10 patients with HTLV-I-associated myelopathy presenting with acquired ichthyosis were assessed by histopathological and immunohistochemical tests. We used anticytokeratin antibodies related to normal keratinization (K1/K10), and others related to cutaneous conditions such as activation, migration and hyperproliferation of keratinocytes (K6/K16), and involucrin, a precursor protein in the formation of the protein envelope in keratinocytes. For quantification of the proliferating basal and parabasal cells the anti-Ki-67 antibody was employed.

RESULTS

On light microscopy, all skin specimens displayed orthokeratotic hyperkeratosis and hypogranulosis. Three of them presented focal parakeratosis. A slight to moderate perivascular infiltrate of mononuclear lymphocytes was observed in seven cases, three of which showed discrete spongiosis with epidermotropism of lymphocytes. All fragments displayed coexpression of K1, K10 and K16 in the suprabasal layers. Expression of involucrin was also observed in all cases, in the upper spinous and granular layers. Focal expression of K6 was observed in three cases, under a parakeratotic area. The mean number of Ki-67+ basal and parabasal cells was 3.5 cells per mm, similar to that in control skin.

CONCLUSIONS

In acquired ichthyosis related to HTLV-I-associated myelopathy, histopathology revealed orthokeratotic hyperkeratosis and a perivascular inflammatory infiltrate of mononuclear lymphocytes, with areas of parakeratosis and foci of epidermotropism in rare cases. The expression profiles of K1, K10 and involucrin were similar to those in normal skin. The diffuse coexpression of K16 with K1 and K10 throughout the analysed epidermis, as well as the occurrence of restricted areas of parakeratosis expressing K6, indicate the presence of keratinocyte activation with induction of the alternative keratinization pathway, probably dependent on the cytokines liberated by the mononuclear cells of the dermal inflammatory infiltrate infected with HTLV-I. The absence of acanthosis and of increased cellular kinetics, as shown by the low rate of Ki-67 antigen expression, allow the inference that the pattern of acquired ichthyosis related to HTLV-I-associated myelopathy may be retentional. The observation of foci of parakeratosis expressing K6 in three specimens suggests that, at least in certain areas and in some cases, interference with epidermal differentiation and maturation occurs.

HIV-associated pruritus: etiology and management

With the advent of highly active antiretroviral therapy (HAART), life-threatening opportunistic infection has become less common in patients with HIV infection and longevity has increased dramatically. With increased longevity, the problems of living with a chronic disease have become more prominent in this patient population. Disorders such as fat redistribution and metabolic abnormalities can result from antiviral medications and from HIV disease itself. Pruritus is one of the most common symptoms encountered in patients with HIV. The spectrum of skin diseases in such patients encompasses dermatoses of diverse etiologies; a few are peculiar to patients with HIV while others are not. Some of these conditions may cause severe and sometimes intractable pruritus that provokes scratching, picking, disfigurement, sleep loss, and significant psychological stress. Moreover, the expense of ongoing medical treatments can be daunting. Skin rash can sometimes be the initial presentation of HIV infection or serve as a harbinger of disease progression. Causes of pruritus include skin infections, infestations, papulosquamous disorders, photodermatitis, xerosis, drug reactions, and occasionally lymphoproliferative disorders. Drug eruptions are particularly common in patients who are HIV positive, presumably as a result of immune dysregulation, altered drug metabolism, and polypharmacy. Itching can also result from systemic diseases such as chronic renal failure, liver disease, or systemic lymphoma. Workup of pruritus should include a careful examination of the skin, hair, nails, and mucous membranes to establish a primary dermatologic diagnosis. If no dermatologic cause is found, a systemic cause or medication-related etiology should be sought. Idiopathic HIV pruritus is a diagnosis of exclusion and should only be considered when a specific diagnosis cannot be established. The management of HIV-associated pruritus should be directed at the underlying condition. Phototherapy has been found to be useful in the treatment of several HIV-associated dermatoses and idiopathic pruritus as well. Unfortunately, some of the treatments that have been suggested for patients with HIV are anecdotal or based on small uncontrolled studies. The last decade has seen a surge in the utilization of HAART which, to some degree, reconstitutes the immune system and ameliorates some dermatologic diseases. On the other hand, some skin diseases flare temporarily when HAART is started. Unless frank drug allergy is suspected, HAART does not need to be stopped.