Follicular Atrophy Research Articles

Stress-induced Cushing's syndrome in fur-chewing chinchillas.

One of the most serious problems in the chinchilla industry is 'fur-chewing', when the chinchilla bites off areas of its own or some other animal's fur. The condition generally develops in both genders at the age of 6-8 months. In chinchilla farms in Croatia an incidence of 15-20% has been observed. A pathomorphological, microbiological and parasitological investigation was conducted on eleven 6- to 11-month-old chinchillas of both sexes with clinical symptoms of 'fur-chewing' and three chinchillas without such signs. Histopathology of the adrenal glands and of the chewed skin revealed changes typical of Cushing's syndrome in 'fur-chewed' chinchillas, such as hyperkeratinisation of the epidermis, epidermal atrophy, pronounced follicular and sebaceous gland atrophy, hyperkeratinisation of the follicles with comedo formations and the presence of calcium salts in subcutis.

Morphologic and immunologic characterization of a canine isthmus mural folliculitis resembling pseudopelade of humans.

The clinical, histopathologic and immunopathologic features of a novel form of isthmus mural folliculitis in dogs, which resembles pseudopelade in humans, were characterized. Clinically, dogs exhibited variably distributed foci of alopecia that persisted without treatment or did not respond to immunosuppressive therapy. Histopathologically, mixed mononuclear cell infiltrates, largely lymphocytes, infiltrated the follicular isthmus. Occasionally, inflammation extended above and below the follicular isthmus but did not involve the hair bulb or the epidermis. Severe follicular atrophy and variable atrophy of sebaceous glands occurred in all dogs. Folliculotropic lymphocytes exhibited most commonly CD3 and CD8 (cytotoxic T cells). Autoantibodies specific for the lower hair follicle were detected in the serum of affected patients. Western immunoblotting demonstrated binding of these antibodies to multiple follicular keratinocyte proteins, including hair keratins and trichohyalin. Lack of hair regrowth (in contrast to canine alopecia areata), as well as location of inflammation and extreme atrophy of adnexal units are similar to findings seen in human pseudopelade.

Helicobacter felis infection is associated with lymphoid follicular hyperplasia and mild gastritis but normal gastric secretory function in cats.

The relationship of Helicobacter felis, a bacterium observed in the stomachs of cats, to gastric disease is unclear. The objective of this study was to determine if H. felis infection alters gastric histopathology, proinflammatory cytokine expression, and secretory function and evokes a humoral immune response in cats. Five specific-pathogen-free (SPF) Helicobacter-free cats were studied before and for 1 year after oral inoculation with H. felis (ATCC 49179). Four SPF H. felis-uninfected cats served as controls. The stomachs of all five H. felis-inoculated cats became colonized, as determined by urease activity, histopathology, PCR, culture, and transmission electron microscopy of serial gastric biopsies at 0, 3, 5, 8, and 12 months. Uninoculated cats remained Helicobacter free. Lymphoid follicular hyperplasia, atrophy, and fibrosis were observed primarily in the pylorus of infected cats. Mild mononuclear inflammation was detected in both infected and uninfected cats, but was more extensive in infected cats, with pangastric inflammation, eosinophilic infiltrates, and cardia gastritis observed only in infected cats. No upregulation of antral mucosal interleukin 1alpha (IL-1alpha), IL-1beta, or tumor necrosis factor alpha was detected by reverse transcription-PCR in any cat. The gastric secretory axes, assessed by fasting plasma gastrin, antral mucosal gastrin and somatostatin immunoreactivity, and pentagastrin-stimulated gastric acid secretion, were similar in both infected and uninfected cats. Gradual seroconversion (immunoglobulin G) was observed in four of five infected cats, with enzyme-linked immunosorbent assay values reaching 4x to 12x baseline 12 months postinfection. These findings indicate that H. felis infection in cats induces lymphoid follicular hyperplasia, mild gastritis, and seroconversion, but is associated with normal gastric secretory function.

Follicular dysplasia in two cows.

The histological features of a follicular dysplasia with pigmentary changes is reported in two adult cows, one a black Brangus-cross and the other a black Angus. Adult onset of diffuse alopecia was present in both cows. Skin biopsies exhibited follicular distortion and atrophy, with melanin clumping in follicular epithelium, hair bulb matrix cells, hair shafts, and infundibular keratin. Both animals were clinically normal apart from the alopecia. This report confirms and expands on the infrequently reported syndrome of follicular dysplasia in cattle.

Conradi‐Hünermann Syndrome with Unilateral Distribution

Abstract: Conradi‐Hünermann syndrome is a type of chondrodysplasia punctata characterized by skeletal, cutaneous, and ocular anomalies. Genetic heterogeneity and incomplete penetrance may explain the wide clinical spectrum. We report a 7‐day‐old girl, product of a preterm pregnancy and delivery, with ichthyosiform erythoderma on the right half of the body at birth, as well as patchy cutaneous involvement of the contralateral side. On physical examination, we observed an ipsilateral shortening of the leg and a lenticular opacity of the right eye. Histopathologic study showed parakeratotic hyperkeratosis with prominent follicular involvement and atrophy of the granular and spinous layers. The skin eruption disappeared during the first 2 months. At 2 months of age, radiologic examination revealed stippled calcifications in the ribs, vertebral, and paravertebral areas. The most important differential diagnosis was CHILD syndrome. We emphasize the importance of the histopathologic study in the differential diagnosis of both syndromes.

Linear lichen planopilaris of the face

A 44-year-old man had a 6-month history of an asymptomatic linear erythematous lesion on the right cheek. Examination revealed a linear 0.8 × 8.0 cm area of erythematous follicular papules and atrophy on his right cheek with loss of beard hairs (Fig. 1). The oral mucosa, scalp hair, axilla, pubis, and nails were normal. A biopsy specimen showed a thin epidermis with orthohyperkeratosis. The stratum granulosum was normal. At the dermoepidermal interface hydropic degeneration with sporadic Civatte bodies was observed. In From the Department of Dermatology, University Hospital Nijmegen. Reprints not available from the authors. J Am Acad Dermatol 1998;38:633-5. Copyright © 1998 by the American Academy of Dermatology, Inc. 0190-9622/98/$5.00 + 0 16/54/88866 Linear lichen planopilaris of the face

Thymectomy: its role in the management of myasthenia gravis.

The management and clinical course of patients with myasthenia gravis admitted to a neurological intensive therapy unit (ITU) for thymectomy over a 66 month period were reviewed. There were 53 patients, 20 male and 33 female, mean age 35.2 years (18-74) and median ITU stay of 5 days (2-30). Indications for thymectomy were thymic enlargement on computed tomography (34%), persistence of generalized symptoms (38%), a combination of both (20%), steroid side effects or dependency (4%) and progressive bulbar symptoms (4%). Following thymectomy, thymic histology revealed thymic follicular hyperplasia (26/53; 49%), atrophy (11/53; 21%), thymoma (12/53; 23%) and normal thymus (4/53; 8%). Post-operatively 23% required prolonged intubation (> 48 hrs); two patients required a tracheostomy 10 and 13 days post-operatively. Plasma exchange was required for two patients (3.8%) due to persistent severe myasthenic weakness. Three patients (6%) developed a post-operative chest infection and one pseudomembranous colitis. There were no post-operative mortalities during the study period. After 2 years, 35% of patients were in remission and 46% had ocular or mild generalized symptoms only. Thymectomy for myasthenia gravis is followed by sustained clinical improvement in the majority of patients. The appropriate post-operative management of these patients is best undertaken in a specialized neuro-intensive care setting. Copyright Rapid Science Ltd

Histopathologic Findings in the Lymphoid and Reticuloendothelial System in Pediatric Hiv Infection:. A Postmortem Study

The present report describes the histopathological features of lymphoreticular tissues in 29 pediatric autopsies of human immunodeficiency virus (HIV)-infected patients. Mean age for the whole group was 1.77 years; 68.9% and 62% of the cases were 2 years old or less and 1 year old or less at the time of death, respectively. Twenty-one cases were categorized as acquired immunodeficiency syndrome (AIDS) and the rest included seven HIV-positive newborns and infants and two infants belonging to a high-risk group. The thymus (24 cases) showed severe lymphoid depletion (atrophy) in 16 (66.6%) cases, microcystic transformation of Hassall's corpuscles (HCs) in 4, calcified HCs in 3, absence of HCs in 3, and plasmacytic infiltrates and Warthin-Finkeldey-type multinucleated giant cells (also found in lymph nodes and bowel lymphoid aggregates in the same case) in 1. Lymph nodes (25 cases) revealed extensive lymphocyte depletion (68%); selective follicular (2 cases) or paracortical (3 cases) atrophy; hemophagocytosis (44%); some type of hyperplasia (plasmacytosis, enlarged follicles) in 5 cases; some type of lymphadenitis (12 cases), 5 cases of which were due to opportunistic infections (cytomegalovirus, 2; histoplasmosis, cryptococcosis, Mycobacterium avium-intracellulare, 1 each). Main findings in the spleen (28 cases) were extensive lymphocyte depletion (10 cases), limited to the white pulp in 4 and including the red pulp in 7; some type of lymphoid hyperplasia (limited to white pulp in 6 cases and involving the red pulp in 5); hemophagocytosis (7 cases); and foci exhibiting a peculiar arrangement of spindle-shaped cells combined with capillaries, plasma cells, and occasionally siderophages in 11. These we have termed kaposiform areas due to the resemblance to the so-called inflammatory variant of Kaposi's sarcoma. This pattern was also recognized in lymph nodes of two cases. Although atrophy was the main theme, cases with hyperplasia were also noticed. The possible relationship, if it exists at all, between kaposiform areas and Kaposi's sarcoma remains to be established. No tumor was found in this series. No specific histopathologic pattern of lymphoid tissues atributable to HIV emerged form this study aside from kaposiform areas, a microscopic feature not previously reported in this circumstance in pediatrics.

Characteristics of follicular tumors and nonneoplastic thyroid lesions in children and adolescents exposed to radiation as a result of the chernobyl disaster

In addition to the previously reported increase in incidence of thyroid carcinomas in Belarussian children after the Chernobyl disaster in April, 1986, benign thyroid lesions were also found to be increased in the exposed population. A total of 60 follicular neoplasms and benign nonneoplastic thyroid lesions arising after the Chernobyl disaster in children and adolescents of 7 to 18 years of age were studied. The primary diagnoses in this series were follicular carcinoma in 1 (2%) case, follicular adenoma in 9 (15%), cystic adenomatoid nodule with papillae in 18 (30%), multinodular goiter in 18 (30%), diffuse hyperplasia in 2 (3%), diffuse hyperplasia with atypia and nodularity in 5 (8%), lymphocytic thyroiditis in 6 (10%), and thyroid cyst in 1 patient (2%). Additional histologic changes in thyroid glands from these patients were similar to those reported after radiation exposure, and included perifollicular fibrosis (72%), focal epithelial hyperplasia (73%), colloid accumulation (47%), follicular atrophy (33%), and cellular atypia (25%). Vascular abnormalities were found more often (75%) than previously reported in the thyroid gland after irradiation, and had a somewhat different appearance. They affected primarily medium-size arteries and were characterized by damage of the internal elastic lamina in addition to intimal fibrosis. The first case of thyroid follicular carcinoma in the exposed Belarussian children was diagnosed after a latent period of 6.5 years, as compared with 4 years of minimal latency for post-Chernobyl papillary carcinomas. Among benign thyroid lesions, cystic adenomatoid nodules of papillary type and diffuse hyperplasia with cellular atypia and nodularity seem to be commonly associated with radiation exposure to the thyroid gland.

Effects of zearalenone and/or tamoxifen on swine and mink reproduction.

Tamoxifen (TAM), which binds to estrogen receptors and can act as an estrogen antagonist, was incorporated into the diets of swine and mink to determine if it would ameliorate the effects of the estrogenic mycotoxin zearalenone (ZEN). Sows and female mink were fed diets containing 2 ppm (swine) or 20 ppm (mink) ZEN and/or 10 ppm TAM from day 30 of gestation through weaning (swine) or from 2 months prior to breeding through weaning (mink). The diets containing ZEN and/or TAM did not adversely affect reproduction in the sows. Although some hyperestrogenic effects on testes, uterine and ovarian weights were observed in the F1 piglets at 21 days of age, subsequent breeding performance was not affected. All the female mink exposed to ZEN mated, but only 25% whelped. No mink fed TAM (singly or in combination with ZEN) mated. Necropsy of these unmated females fed TAM revealed consistent severe pyometra. Histological examination of the reproductive tracts of the ZEN, TAM and ZEN + TAM-treated mink showed similar alterations, including ovarian follicular atrophy and degeneration, and mild to severe uterine atrophy, pyometra and endometritis. The results of these studies indicate that TAM was not effective in ameliorating the hyperestrogenic effects of ZEN in swine and mink, but rather it acted as an estrogen agonist.

Protection by α-tocopherol against skin ulcers induced by ionizing radiations

An in vivo study was carried out to determine the protective character of α-tocopherol against lesions caused by free radicals of ionizing radiation. Emulsified vehicles (o/w) were used at dosages of 1.5 and 2.5% w/w of α-tocopherol. To promote generation of free radicals, we used 6 MeV electrons from a lineal accelerator; a dosage of 2800 cGy was selected. The lesions were assessed according to the indications of the WHO, modified for such an effect. Biopsies of the treated areas were taken at the moment of maximum acute toxicity in order to subject them to an anatomopathological study, evaluating five parameters: thickness of epidermis, squamous metaplasia of the adnexa, overall impression, follicular atrophy and density of fibroblasts. The conclusions of this study indicate that under the experimental conditions used, α-tocopherol, applied topically, protects the skin from ionizing radiation, giving rise to a thicker epidermis than found in healthy animals.

Hormonal abnormalities in Pomeranians with normal coat and in Pomeranians with growth hormone-responsive dermatosis

Summary Clinical status, skin biopsy specimens, and endocrine function were evaluated in normal-coated Pomeranians (n = 12) and Pomeranians affected with growth hormone (gh)-responsive dermatosis (n = 7), then were compared with values in mixed-breed dog controls (n = 19). All Pomeranians were clinically normal; however, the Pomeranians with gh-responsive dermatosis had bilateral alopecia and hyperpigmentation of the trunk, caudal portion of the thighs, and ventral neck region. Skin biopsy specimens from the affected Pomeranians had decreased-to-normal epidermal thickness and follicular atrophy, compared with normal-coated Pomeranians. Numerous elastin fibers were observed in the skin biopsy specimens of unaffected and affected Pomeranians. Both groups of Pomeranians had normal results of thyrotropin-releasing hormone (trh) and thyrotropin (tsh) response, adrenocorticotropin (acth) stimulation, and dexamethasone suppression testing. There was no significant increase in serum gh concentration in either group of Pomeranians after xylazine or human GH-releasing factor (ghrf) administration, whereas control dogs had significant (P ≤ 0.05) increase in serum gh concentration after administration of either agent. Baseline plasma acth concentration in unaffected and affected Pomeranians was increased above the normal range (40 to 90 pg/ml). Post-acth administration serum progesterone, 17-hydroxyprogesterone, and androgen (dehydroepiandrosterone sulfate or androstenedione) concentrations were consistently high in unaffected and affected Pomeranians, compared with values in control dogs. High baseline plasma acth concentration and increased production of progesterone, 17-hydroxyprogesterone, and dehydroepiandrosterone sulfate or androstenedione after acth administration suggested disregulation of adrenocortical hormone synthesis in both groups of Pomeranians, possibly attributable to partial deficiency of the 21-hydroxylase enzyme. Although all 3 treated dogs developed normal coat in response to supplementation with human gh, gh-responsive dermatosis in Pomeranians may not be entirely attributable to hyposomatotropism, but may also involve adrenocortical hyperprogestinism and/or hyperandrogenism.

Toxicity of 4-vinyl-1-cyclohexene diepoxide after 13 weeks of dermal or oral exposure in rats and mice

4-Vinyl-1-cyclohexene diepoxide (VCHD) is used as a chemical intermediate and as a reactive diluent for diepoxides and epoxy resins. Toxicology studies were conducted by administering VCHD in acetone by dermal application or in corn oil by gavage to F344 N rats and B6C3F1 mice for 13 weeks. In the 13-week dermal studies, groups of 10 rats of each sex received 0.3 ml of VCHD in acetone at concentrations ranging from 6.25 to 200 mg/ml, and mice received 0.1 ml at concentrations ranging from 6.25 to 100 mg/ml. Skin lesions were observed at the site of application at the top two dose levels for both species and sexes, and consisted of acanthosis, parakeratosis, and hyperkeratosis of the epidermis and sebaceous gland hyperplasia. In mice, follicular atrophy of the ovary, characterized by decreased numbers of primary and secondary follicles, occurred at the 50- and 100-mg dose levels, In 13-week oral studies, groups of 10 rats and mice of each sex were administered VCHD at dose levels ranging from 62.5 to 1000 mg/kg in corn oil. In rats and mice, there were body weight decreases in the groups given the two highest doses. The major target organs in rats were forestomach (hyperplasia and hyperkeratosis) and kidney (tubular cell degeneration/necrosis and regeneration). In mice the target organs included forestomach (hyperplasia and hyperkeratosis), ovary (follicular atrophy), and testis (degeneration of germinal epithelium).

Toxicity of 4-Vinyl-1 -cyclohexene Diepoxide after 13 Weeks of Dermal or Oral Exposure in Rats and Mice

Toxicity of 4-Vinyl-1-cyclohexene Diepoxide after 13 Weeks of Dermal or Oral Exposure in Rats and Mice. CHHABRA, R.S., ELWELL, M. R., AND PETERS, A. (1990). Fundam. Appl. Toxicol. 14, 745–751. 4-Vinyl-1 -cyclohexene diepoxide (VCHD) is used as a chemical intermediate and as a reactive diluent for diepoxides and epoxy resins. Toxicology studies were conducted by administering VCHD in acetone by dermal application or in com oil by gavage to F344/N rats and B6C3F1 mice for 13 weeks. In the 13-week dermal studies, groups of 10 rats of each sex received 0.3 ml of VCHD in acetone at concentrations ranging from 6.25 to 200 mg/ml, and mice received 0.1 ml at concentrations ranging from 6.25 to 100 mg/ml. Skin lesions were observed at the site of application at the top two dose levels for both species and sexes, and consisted of acanthosis, parakeratosis, and hyperkeratosis of the epidermis and sebaceous gland hyperplasia. In mice, follicular atrophy of the ovary, characterized by decreased numbers of primary and secondary follicles, occurred at the 50- and 100-mg dose levels. In 13-week oral studies, groups of 10 rats and mice of each sex were administered VCHD at dose levels ranging from 62.5 to 1000 mg/kg in corn oil. In rats and mice, there were body weight decreases in the groups given the two highest doses. The major target organs in rats were forestomach (hyperplasia and hyperkeratosis) and kidney (tubular cell degeneration/necrosis and regeneration). In mice the target organs included forestomach (hyperplasia and hyperkeratosis), ovary (follicular atrophy), and testis (degeneration of germinal epithelium).

Role of adjuvants in inhibitory influence of immunization with porcine zona pellucida antigen (ZP-3) on ovarian folliculogenesis in bonnet monkeys: a morphological study.

Female bonnet monkeys were immunized with 55 kDa porcine zona antigen (ZP-3), with either complete Freund's adjuvant (CFA) or sodium phthalylated lipopolysaccharide (SPLPS) as adjuvant. Anti-ZP-3 antibody titers were monitored and the effect of immunization on the ovarian morphology was assessed by high-resolution light microscopy. The study demonstrated that both adjuvants used were equally potent in eliciting antibody response against ZP-3. Although no morphological damage to ovarian components was observed in animals immunized with SPLPS as adjuvant, immunization using CFA resulted in profound ovarian follicular atrophy, sparing only the primordial follicles. The atrophic phenomenon involved those follicles that either already had or were in the process of forming zona pellucida. The results of this study indicate that choice of adjuvant may be an important consideration for immunization against zona antigens. These findings encourage further investigations for developing better immunization regimen aimed at using zona antigens for immunocontraception.

Linear lichen planopilaris of the face

A 44-year-old man had a 6-month history of an asymptomatic linear erythematous lesion on the right cheek. Examination revealed a linear 0.8 × 8.0 cm area of erythematous follicular papules and atrophy on his right cheek with loss of beard hairs (Fig. 1). The oral mucosa, scalp hair, axilla, pubis, and nails were normal. A biopsy specimen showed a thin epidermis with orthohyperkeratosis. The stratum granulosum was normal. At the dermoepidermal interface hydropic degeneration with sporadic Civatte bodies was observed. In From the Department of Dermatology, University Hospital Nijmegen. Reprints not available from the authors. J Am Acad Dermatol 1998;38:633-5. Copyright © 1998 by the American Academy of Dermatology, Inc. 0190-9622/98/$5.00 + 0 16/54/88866 Linear lichen planopilaris of the face

Effect of gossypol on the thyroid in young rats

The effect of gossypol on thyroid structure and function was examined. Groups of young male rats were subcutaneously injected daily with 0·2 ml gossypol acetic acid in doses of 1, 5, or 10 mg per kg body weight. Control rats were injected with vehicle only. At the end of the 15-day treatment, there was a dose-dependent decrease in the serum concentrations of thyroid hormones, i.e., free thyroxine, triiodothyronine, and reverse triiodothyronine. Histopathological examination revealed focal degeneration of thyroid follicles after a dose of 1 mg gossypol per kg body weight; widespread follicular atrophy occurred with 5 mg and 10 mg gossypol per kg body weight. The degenerating follicles were lined with discontinuous cuboidal or squamous follicular epithelium, some of which exfoliated into colloid.

Pathology of two possible genodermatoses

ABSTRACTA United Kingdom bred Shetland sheepdog puppy was presented with crusting, hyper‐ and hypopigmented alopecic skin lesions on the face, nose, tail and extensor surfaces of the lower limbs. Histologically, the lesions were characterised by vacuolation of the basal epidermis with formation of colloid bodies and vesication. There was accompanying dermal oedema with moderate infiltrates of predominantly mononuclear cells. Hyperpigmentation, acanthosis and follicular atrophy correlated with the clinical appearance of chronic lesions. Skin scrapings for ringworm and mites were negative as was direct immunofluorescence. A full post mortem examination was conducted. Histological examination of five muscle sites, including the temporalis and masseter muscles did not show any significant abnormality. The condition is discussed in relation to the pathological criteria required for diagnosis and compared with published reports of epidermolysis bullosa and dermatomyositis in collies and Shetland sheepdogs. Confirmation of the clinical diagnosis of cutaneous asthenia (Ehlers‐Danlos syndrome) was made pathologically in two domestic shorthaired cats from the same area of the United Kingdom. Histological and electron microscopic findings are described and compared with other published reports.

Follicular involution in HIV lymphadenopathy. A morphometric study.

Lymph node biopsies from 75 HIV infected patients (71 homo- and bisexual men, 3 hemophiliacs and 1 woman) were studied using immunohistochemical methods with monoclonal antibodies (Mabs) against B lymphocytes, subsets of T lymphocytes, follicular dendritic cells (FDC) and HIV gag proteins p24 and p18. Histopathological changes were classified as follicular hyperplasia (FH), fragmentation (FF), atrophy (FA) and depletion (FD). Immunohistochemical stainings were quantified with the help of an Image Quantifier (IQ) and the reactivity for respective Mab-defined antigen was related quantitatively to other antigens and histopathological changes. Such measurements showed an increase in FDC in biopsies with FH and FF histology and a decrease in FA and FD cases in comparison with cases with non-HIV related lymphadenopathy. In addition it was found that the decrease in FDC was correlated with an increase in CD8+ within the follicles. Double immunostainings for p24 and various cellular markers showed that p24 was predominantly associated with follicular dendritic cells. Essentially the same findings were observed in the lymph nodes irrespective of risk group. Possible mechanisms involved in follicular involution in HIV-related lymphadenopathy are discussed.

HISTOPATHOLOGY AND IMMUNOHISTOLOGY OF HTLV‐III/LAV RELATED LYMPHADENOPATHY AND AIDS.

Fifty-nine lymph node biopsies from homosexual men with serum antibodies to HTLV-III/LAV were the subject of a detailed histopathological and immunohistochemical study. The histological findings were correlated to the patients clinical status, and the T4/T8 ratios in blood and lymph nodes. Four histological patterns predominated and were defined as follicular hyperplasia (FH), follicular fragmentation (FF), follicular atrophy (FA), and follicular depletion (FD). Immunocytochemical studies indicated that destruction of follicular dendritic cells is related to the initiation of follicular involution from FH to FF, but the possible role of follicular infiltrating T-cells cannot be excluded. Marked individual variations in lymph node angiogenesis increasing during involution were observed, which suggests that the degree of angiogenic host response may predispose for evolution of Kaposi's sarcoma. The majority of the patients with the clinical diagnosis of persistent generalized lymphadenopathy (PGL) were morphologically staged as FH or FF (89%), whereas most of the AIDS patients showed lymph node changes compatible with FA and FD (89%). Patients with AIDS-related complex (ARC) had a wider spectrum of morphological lymph node changes but a majority of cases (62%) were also classified as FA or FD. Clinical follow-up showed progression from PGL to ARC in seven of 21 cases with the FF pattern and only in three of 19 cases with FH, indicating a possible prognostic value in differentiating between FH and FF. Three cases with FD and one with FA progressed to AIDS during the time of observation. T4/T8 ratios in blood and lymph nodes were significantly lower in patients with FD histology compared to patients of the other histological groups. At autopsy, all AIDS cases showed the FD pattern of lymphadenopathy. Autopsy findings in seven patients emphasized the importance of post-mortem studies in clarifying the spectrum of opportunistic diseases, including tumors which afflict the AIDS patients.