Page 570 - Concise Pathology for Exam Preparation ( PDFDrive )

20 Endocrinology 555

(iv) Infections (AIDS, tuberculosis, fungi and acute haemorrhagic necrosis)
(v) Amyloidosis, sarcoidosis and haemochromatosis
(vi) Metastatic carcinoma
(b) Causes of secondary insufficiency:
(i) Hypothalamic pituitary disease, neoplasms and inflammation (sarcoidosis,
tuberculosis, pyogenic and fungal)
(ii) Hypothalamic pituitary suppression (long-term steroid administration and
steroid-producing neoplasms)
2. Acute and chronic insufficiency, based on onset and duration.
(a) Acute adrenal insufficiency or adrenal crisis:
Causes
• Bilateral adrenalectomy
• Septicaemia, eg, endotoxic shock and meningococcal infection
• Rapid withdrawal of steroids
• Acute stress in chronic deficiency
Clinical features
• Deficiency of mineralocorticoids results in salt deficiency, hyperkalaemia and dehy-
dration
• Deficiency of glucocorticoids results in hypoglycaemia, increased insulin sensitivity
and vomiting
(b) ‘Chronic adrenal insufficiency’ or Addison disease: Clinical manifestations do not
appear till 90% gland (adrenal cortex) is compromised.
Causes
• Lymphomas
• Amyloidosis
• Sarcoidosis
• Haemochromatosis
• Fungal infections
• Adrenal haemorrhage
• More than 90% cases are due to autoimmune adrenalitis, tuberculosis and meta-
static cancer
Morphology
• Irregularly shrunken glands are difficult to identify in the suprarenal adipose tissue.
• Cortex contains only scattered residual cortical cells in a collapsed network of con-
nective tissue.
• Variable lymphoid infiltrate may be seen.

Q. Write briefly on Waterhouse–Friderichsen syndrome.
Ans. Uncommon and catastrophic syndrome with the following characteristics:
• May affect any age group but is common in children.
• Usually follows overwhelming bacterial infection due to Neisseria meningitidis, Pseudo-
monas, pneumococci, Haemophilus influenzae and Staphylococci.
• Presents with rapidly progressing hypotension, shock, DIC and widespread purpura
due to rapidly progressing adrenocortical insufficiency and massive bilateral adrenal
haemorrhage (adrenals converted to sacs of blood).
• Direct bacterial seeding of small vessels in adrenals may lead to DIC.
• Thought to be endotoxin-induced or hypersensitivity-mediated vasculitis.
• Clinical course abrupt; early recognition and institution of appropriate therapy is a must.

Q. Enumerate adrenocortical neoplasms and describe their salient
features.

Ans. Adrenocortical neoplasms include
1. Adrenocortical adenoma
(a) Indistinguishable from hyperplastic nodules except that hyperplastic nodules tend
to be smaller than 2 cm.
(b) Most adenomas are slow growing and nonfunctional; a few larger ones may be
functional.

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