Section 5 Immunodeficiency
1. Primary immunodeficiency
(1) Pure immunoglobulin deficiency
① Bruton-type gammaglobulinaemia
② Hypogammaglobulinaemia of late onset
③ Dysgammaglobulinaemia
In these disorders these is susceptibility to
bacterial and yeast infections, but viral
infections are controlled normally. Cellmediated reactions are intact.
(2) Pure T-cell deficiency
① Thymic agenesis
② Thymic alymphoplasia (dysplasia)
③ Thymic hypoplasia or aplasia
Here the immunoglobulin levels are
normal but there is a complete absence of
cell-mediated reactions
(3) Mixed deficiency
2. Secondary immunodeficiency
Resulting from:
(1) Excessive loss of immunoglobulins
① Protein-losing enteropathy
② Nephrotic syndrome
(2) Depression of the immune system by
① Old age
② Malnutrition
③Viral infections such as acquired
immunodeficiency syndrome.
④ Leprosy
⑤ Malaria
⑥ Sarcoidosis
⑦ Surgery
⑧ Uraemia
(3) Immunosuppression by
① X-rays
② Corticosteroids
③ Cytotoxic drugs
④ Antilymphocyte serum
⑤ Anntimetabolits
(4) Neoplasia
① Hodgkin’s disease
② Multiple myeloma
③ Waldenstrom’s macroglobulinaemia
④ Chronic lymphatic leukaemia
(5) Splenectomy
Acquired Immunodeficiency
Syndrome (AIDS)
In June 1981, the centers for disease
control of the United States reported that
five young homosexual men in the Los
Angeles area had contracted the AIDS
Etiology: human immunodeficiency virus
(HIV)
HIV （from Robbins Basic Pathology ,2003）
Features:
① A long incubation period, followed by a
slowly progressive fatal outcome.
② Tropism for hematopoietic and nervous
systems
③ An ability to cause immunosuppression
④ Cytopathic effects in vitro.
Epidemiology
Worldwide: about 10 million people are infected.
Five groups of adults at high risk for developing
AIDS:
① Homosexual or bisexual males
② Intravenous drug abusers
③ Hemophiliacs
④ Recipients of blood and blood components
⑤ Heterosexual contacts
Pathogenesis
HIV→CD4+ cell→ CD4+ cell lysis →
opportunistic infections and neoplasms
Morphology
Neither specific nor diagnostic.
① Widespread opportunistic infections
② Kaposi’s sarcoma
③ Lymphoid tumors
The multiple effects of loss of CD4+ T cells as a result of HIV infection
(From Robbins Basic Pathology ,2003）
Slide 7.41
AIDS with Kaposi sarcoma
Kaposi sarcoma in liver of AIDS patients
AIDS with herpes
Offered by Prof Song W Wong
AIDS-related Marked follicular hyperplasia (early stages)
HIV infection showing the formation of giant cells in the brain.
(Dr. Dennis Burns) . (From Robbins Basic Pathology ,2003）
Slide 7.40
Lymph nodes:
Marked follicular hyperplasia (early
stages)→ Lymphoid cells depletion
(empty-looking lymph nodes or spleen
and thymus in later stages).
Mortality: 100%