Other lung diseases

1.Sarcoidosis

1. Sarcoidosis

a. More common in African-Americans.

b. Associated with the presence of noncaseating granulomas.

Sarcoidosis is an immune system disorder characterised by non-necrotising granulomas (small inflammatory nodules). Virtually any organ can be affected, however, granulomas most often appear in the lungs or the lymph nodes.

Signs and symptoms

• Sarcoidosis is a systemic disease that can affect any organ. Common symptoms are vague, such as fatigue unchanged by sleep, lack of energy, aches and pains, dry eyes, blurry vision, shortness of breath, a dry hacking cough or skin lesions. The cutaneous symptoms are protean, and range from rashes and noduli (small bumps) to erythema nodosum or lupus pernio
• Renal, liver, heart or brain involvement may cause further symptoms and altered functioning. Manifestations in the eye include uveitis and retinal inflammation
• Sarcoidosis affecting the brain or nerves is known as neurosarcoidosis.
• Hypercalcemia (high calcium levels) and its symptoms may be the result of excessive vitamin D production
• Sarcoidosis most often manifests as a restrictive disease of the lungs, causing a decrease in lung volume and decreased compliance (the ability to stretch). The vital capacity (full breath in, to full breath out) is decreased, and most of this air can be blown out in the first second. This means the FEV1/FVC ratio is increased from the normal of about 80%, to 90%.

Treatment

Corticosteroids, most commonly prednisone

2. Cystic fibrosis

a. Transmission: caused by a genetic mutation (nucleotide deletion) on chromosome 7, resulting in abnormal chloride channels.

b. The most common hereditary disease in Caucasians.

c. Genetic transmission: autosomal recessive.

d. Affects all exocrine glands. Organs affected include lungs, pancreas, salivary glands, and intestines. Thick secretions or mucous plugs are

seen to obstruct the pulmonary airways and intestinal tracts.

e. Is ultimately fatal.

f. Diagnostic test: sweat test—sweat contains increased amounts of chloride.

3. Atelectasis

a. Characterized by collapse of the alveoli.

b. May be caused by a deficiency of surfactant and/or hypoventilation of alveoli.

Lymphomas

A. Hodgkin’s disease

1. Characterized by enlarged lymph nodes and the presence of Reed-Sternberg cells (multinucleated giant cells) in lymphoid tissues.

2. Disease spreads from lymph node to lymph node in a contiguous manner.

3. Enlarged cervical lymph nodes are most commonly the first lymphadenopathy observed.

4. The cause is unknown.

5. Occurs before age 30.

6. Prognosis of disease depends largely on the extent of lymph node spread and systemic involvement.

B. Non-Hodgkin’s lymphoma

1. Characterized by tumor formation in the lymph nodes.

2. Tumors do not spread in a contiguous manner.

3. Most often caused by the proliferation of abnormal B cells.

4. Occurs after age 40.

5. Example: Burkitt’s lymphoma

a. Commonly associated with an EpsteinBarr virus (EBV) infection and a genetic mutation resulting from the translocation of the C-myc gene from chromosome 8 to 14.

b. The African type occurs in African children and commonly affects the mandible or maxilla.

c. In the United States, it most commonly affects the abdomen.

d. Histologically, the tumor displays a  characteristic “starry-sky” appearance.

Immunoglobulins. (Ig)

 These are made up of polypeptide chains. Each molecule is constituted by two heavy and two light chains, linked by disulfide (S-S) bonds. The h~ chains are of 5 types, with corresponding, types or  immunoglobulin. IgG (gamma), IgM (mu µ ), IgA(alpha α), IgD(delta ), IgE(epsilon)

Each of these can have light chains of either kappa (k) or lambda type.Each chain has a constant portion (constant for the subtype) land a variable portion (antigen specific).

Enzyme digestion can split the Ig molecule into.2 Fab (antibody binding) fragments and one Fc (crystallisable, complement binding ) fragment.

Multiple Endocrine Neoplasia Syndromes (MEN)

The MEN syndromes are a group of inherited diseases resulting in proliferative lesions (hyperplasias, adenomas, and carcinomas) of multiple endocrine organs. Even in one organ, the tumors are often multifocal. These tumors are usually more aggressive and recur in a higher proportion of cases than similar but sporadic endocrine tumors. 

Multiple Endocrine Neoplasia Type 1 (MEN1) is inherited in an autosomal dominant pattern. The gene (MEN1) is a tumor suppressor gene; thus, inactivation of both alleles of the gene is believed to be the basis of tumorigenesis. Organs commonly involved include the parathyroid, pancreas, and pituitary (the 3 Ps). Parathyroid hyperplasia is the most consistent feature of MEN-1 but endocrine tumors of the pancreas are the leading cause of death because such tumors are usually aggressive and present with metastatic disease.

Zollinger-Ellison syndrome, associated with gastrinomas, and hypoglycemia, related to insulinomas, are common endocrine manifestations. Prolactin-secreting macroadenoma is the most frequent pituitary tumor in MEN-1 patients. 

Multiple Endocrine Neoplasia Type 2 (MEN2)

MEN type 2 is actually two distinct groups of disorders that are unified by the occurrence of activating mutations of the RET protooncogene. Both are inherited in an autosomal dominant pattern. 

MEN 2A

Organs commonly involved include:

Medullary carcinoma of the thyroid develops in virtually all cases, and the tumors usually occur in the first 2 decades of life. The tumors are commonly multifocal, and foci of C-cell hyperplasia can be found in the adjacent thyroid. Adrenal pheochromocytomas develop in 50% of patients; fortunately, no more than 10% are malignant. Parathyroid gland hyperplasia with primary hyperparathyroidism occurs in a third of patients. 

Multiple Endocrine Neoplasia, Type 2B 

Organs commonly involved include the thyroid and adrenal medulla. The spectrum of thyroid and adrenal medullary disease is similar to that in MEN-2A. However, unlike MEN-2A, patients with MEN-2B: 

1. Do not develop primary hyperparathyroidism
2. Develop extraendocrine manifestations: ganglioneuromas of mucosal sites (gastrointestinal tract, lips, tongue) and marfanoid habitus 

HERPES ZOSTER (Shingles)

An infection with varicella-zoster virus primarily involving the dorsal root ganglia and characterized by vesicular eruption and neuralgic pain in the dermatome of the affected root ganglia.

caused by varicella-zoster virus

Symptoms and Signs

Pain along the site of the future eruption usually precedes the rash by 2 to 3 days. Characteristic crops of vesicles on an erythematous base then appear, following the cutaneous distribution of one or more adjacent dermatomes

Eruptions occur most often in the thoracic or lumbar region and are unilateral. Lesions usually continue to form for about 3 to 5 days

Geniculate zoster (Ramsay Hunt's syndrome) results from involvement of the geniculate ganglion. Pain in the ear and facial paralysis occur on the involved side. A vesicular eruption occurs in the external auditory canal, and taste may be lost in the anterior two thirds of the tongue

Biochemical examination

This is a method by which the metabolic disturbances of disease are investigated by assay of various normal and abnormal compounds in the blood, urine, etc.