AIDS-associated Kaposi's sarcoma and the mechanisms of interferon alpha's activity; a riddle within a puzzle

Anterior Segment and External Ocular Disorders Associated with Human Immunodeficiency Virus Disease

The eye is a common site for complications of human immunodeficiency virus (HIV) infection. Although cytomegalovirus retinitis remains the most prevalent of the blinding ocular disorders that can occur in individuals with the acquired immunodeficiency syndrome (AIDS), several important HIV-associated disorders may involve the anterior segment, ocular surface, and adnexae. Some of these entities, such as Kaposi sarcoma, were well described, but uncommon, before the HIV epidemic. Others, like microsporidial keratoconjunctivitis, have presentations that differ between affected individuals with HIV disease and those from the general population who are immunocompetent. The treatment of many of these diseases is challenging because of host immunodeficiency. Survival after the diagnosis of AIDS has increased among individuals with HIV disease because of more effective antiretroviral therapies and improved prophylaxis against, and treatment of, opportunistic infections. This longer survival may lead to an increased prevalence of anterior segment and external ocular disorders. In addition, the evaluation and management of disorders such as blepharitis and dry eye, which were previously overshadowed by more severe, blinding disorders, may demand increased attention, as the general health of this population improves. Not all individuals infected with HIV receive potent antiretroviral therapy, however, because of socioeconomic or other factors, and others will be intolerant of these drugs or experience drug failure. Ophthalmologists must, therefore, still be aware of the ocular findings that develop in the setting of severe immunosuppression. This article reviews the spectrum of HIV-associated anterior segment and external ocular disorders, with recommendations for their evaluation and management.

A pilot study to test the efficacy of oral administration of interferon-alpha lozenges to patients with Sjögren's syndrome

BACKGROUND

Complications from Sjögren's syndrome-induced xerostomia may cause a significant disruption in daily routines such as speech and eating habits. In addition, the reduction in salivary output may lead to increased incidence of caries, oral ulcers, sialadenitis, periodontal problems, and Candida infections. Interferon-alpha has been suggested as an effective drug therapy to increase salivary output.

OBJECTIVE

The objective was to test the efficacy of interferon-alpha lozenges in relieving the symptoms of dry mouth and dry eyes when administered orally to patients with Sjögren's syndrome in double-blind placebo-controlled and open-label trials.

STUDY DESIGN

Twelve patients with a diagnosis of primary Sjögren's syndrome were provided an Institutional Review Board-approved, written informed-consent form. During the double-blind placebo-controlled study they were randomized to receive 150 IU of interferon-alpha (8 patients) or placebo (4 patients) for 24 weeks with 6-week reevaluations. Five patients who received interferon-alpha in the double-blind placebo-controlled trial were treated in an open-label study for another 24 weeks. Whole saliva was measured during each visit, and symptoms were assessed by questionnaires and visual analog scales. The Wilcoxon signed rank test was used to detect significant changes for each variable.

RESULTS

The results indicated that, by the end of 24 weeks, patients who received interferon-alpha had a statistically significant improvement in unstimulated salivary flow rate (P < .05), and statistically significant changes were observed in the median ocular dryness visual analog scale (P < .05) and oral dryness visual analog scale (P < .05). No significant changes were observed among the placebo patients. By the end of 48 weeks, medicated patients had better results than they had at the end of the double-blind placebo-controlled study and showed improvements in whole stimulated salivary flow rate, conditions of throat, and swallowing dry food.

CONCLUSION

Oral administration of 150 IU interferon-alpha 3 times a day for the patients with primary Sjögren's syndrome improved saliva production, relieved symptoms of xerostomia and xerophthalmia, and was well tolerated by the patients.

Interferon-alpha, unlike interferon-gamma, does not cause bone loss in the rat

Interferons (IFN) are a group of related glycoproteins. IFN-gamma, in vitro, has been shown to inhibit resorption; however, an in vivo experiment showed that it had the opposite effect, resulting in bone loss that was comparable to that caused by cyclosporine A. IFN-alpha has numerous clinical applications but is used most extensively in the treatment of chronic hepatitis B and chronic hepatitis C. Research into the effects of IFN-alpha on bone mineral metabolism has been very sparse, and the majority of studies reflect in vitro models. Like IFN-gamma, there exists discordance between in vitro and in vivo studies on IFN-alpha. Both in vivo and in vitro studies demonstrate that IFN-alpha decreases bone resorption, whereas osteoblasts may or may not be affected in vivo. This study was designed to provide information on the in vivo effects of IFN-alpha in the rat model, because we feel that, given its widespread clinical use, this is an extremely important issue. Rats were given low dose IFN-alpha (1.6 x 10(6) IU/m2), intermediate dose IFN-alpha (5.35 x 10(6) IU/m2), and high dose IFN-alpha (30 x 10(6) IU/m2) three times per week for 28 days. Serum osteocalcin (bone gla protein, or BGP) and parathyroid hormone (PTH) were measured serially and, after double labeling, the bones were examined histomorphometrically. IFN-alpha did not alter any of the histomorphometric parameters measured and did not affect PTH. However, it produced a disparate BGP response. Low dose IFN-alpha resulted in a statistically significant increase in serum BGP on days 14 and 28, whereas intermediate and high doses of IFN-alpha did not. Overall, these results provide no evidence of a deleterious effect of IFN-alpha on bone metabolism and confirm the limited clinical study.

Correlation between tumour and serum beta 2m expression in patients with breast cancer

HLA class I antigens are composed of a major histocompatibility complex (MHC) encoded heavy chain that is associated non-covalently with a light chain beta-2 microglobulin (beta-2m). When the HLA complex is metabolized, beta-2m is shed into the serum. A large variety of human and experimental tumours have altered MHC class I expression. In a previous study we observed elevated mean beta-2m serum levels in breast cancer patients, as compared to controls. To study the relationship between tumour expression and serum levels, we examined 54 patients with breast cancer. Tumour beta-2m was determined by immunohistochemistry and serum levels by the ELISA technique. Of the 54 patients, 38 had low and 16 had high beta-2m expression on the tumour. There was a significant correlation between tumour beta-2m and serum beta-2m levels (P = 0.02), with patients whose tumours expressed high beta-2m having high serum beta-2m levels. There was an inverse correlation between tumour grade and tumour beta-2m expression which approached statistical significance (P = 0.06). These findings suggest that in a substantial number of patients the high serum levels derive from shedding of beta-2m from tumour cells. These levels may have implications for tumour growth and metastases due to influences on immunological responses.

Epidemic AIDS-related Kaposi's sarcoma in southern Africa: experience at the Johannesburg General Hospital (1980-1990)

Epidemic acquired immune deficiency syndrome-related Kaposi's sarcoma (AKS) in tropical and southern Africa is a highly varied neoplastic disease, characterized by multifocal mucocutaneous, lymphatic and visceral involvement. It follows a clinical course similar to AKS in Europe and the USA. However, lack of adequate medical facilities in many African countries hampers successful palliation of this fatal disease. In this retrospective analysis, we summarize our experience with 52 patients with AKS treated at Johannesburg General Hospital, South Africa, between 1980 and 1990. Radiation therapy can provide good to excellent palliation with only minimal side-effects, producing a lesser impact on the haematological and immunological system than chemotherapy.