Page 210 - AIDSBK23C

Page 210

ENDOCRINE ORGAN PATHOLOGY IN AIDS

Most opportunistic infections and neoplasms affecting the endocrine system in patients
with AIDS occur when those diseases are widely disseminated. The most common endocrine
organ affected is the adrenal gland (Table 5). A variety of endocrine disorders can be identified
in patients with HIV infection and AIDS.[773,864,865]

ADRENAL.—Clinically apparent adrenal failure may require destruction of up to 90% of
the parenchyma from pathologic processes seen with AIDS. However, frank adrenal
insufficiency is rare and serum cortisol is usually not markedly reduced during the course of HIV
infection. Most HIV-infected persons have normal to elevated basal cortisol levels, probably
from the stress of the complications of this illness, but reduced cortisol levels may also occur.
HIV infectio of macrophages can increase IL-1 and TNF secretion, and both these cytokines can
stimulate the adrenal. HIV infection of the brain can involve the median eminence, where IL-1
production may stimulate corticotropin releasing hormone leading to increased ACTH release
from the pituitary.[865,866]
Maximum cortisol levels and the rise of serum cortisol appear to be diminished with HIV
infection. Reduction in peak cortisol levels may affect 30% of AIDS patients Evidence of some
degree of adrenal failure with decreased cortisol and electrolyte alterations, such as
hyponatremia, occurs in a majority of patients dying with AIDS. Hyporeninemic
hypoaldosteronism of unknown cause has occasionally been observed to account for persistent
hyperkalemia in AIDS.[773,864]
Drug-induced abnormalities can occur. The antifungal agent ketoconazole can be
responsible for a reversible decrease in cortisol and aldosterone production, but it is rarely the
cause for adrenal insufficiency. Rifampin therapy in patients with Mycobacterium tuberculosis
infection has rarely been reported to cause adrenal crisis.[864]
Grossly, lesions of the adrenal are difficult to detect. Marked adrenal enlargement from
any opportunistic infection is not common. Malignant lymphomas can on occasion cause
unilateral or bilateral enlargement with white-tan to red variegated masses or infiltrates.
Cytomegalovirus may produce a multifocal reddish mottling within the yellow cortex. Kaposi's
sarcoma may infiltrate the periadrenal fat or the substance of the gland in a linear dark-red to
purple pattern. Adrenal glands may become enlarged because of stress in AIDS, though the total
weight of both glands rarely exceeds 20 g.
Cytomegalovirus is the most common endocrine manifestation of AIDS at autopsy,
occurring about three fourths of the time when CMV infection is present at autopsy.
Identification of CMV within the adrenal glands may help to establish the diagnosis of AIDS,
since adrenal may sometimes be the only tissue involved with this opportunistic agent.
Cytomegalovirus may affect either the medulla or the cortex, or both. The medulla is more
likely to be involved initially, with the cortex involved in a longer course or with more extensive
infection. Hyponatremia with hypoglycemia may suggest adrenal insufficiency from
involvement by cytomegalovirus.[419]
Microscopic changes found with CMV infection of adrenals vary from virtually no tissue
reaction, through isolated clusters of small lymphocytes or focal hemorrhages, to extensive
necrosis with polymorphonuclear infiltrates, to extensive fibrosis of cortex or medulla. These
lesions may be accompanied by central venous thrombosis. The most common manifestation of