Neutropenia: Neutropenia is an abnormally low number of neutrophils  
Causes

-Typhoid, paratyphoid. .
-Viral and ricketseal infections.
-Malaria, Kala azar.
-Hypersplenism.
-Aplastic and megaloblastic anaemia.
-Marrow infiltration by malignancies, lymphomas etc.
-SLE.

Acne vulgaris is a chronic inflammatory disorder usually present in the late teenage years characterized by comedones, papules, nodules, and cysts.
 - subdivided into obstructive type with closed comedones (whiteheads) and open comedones (blackheads) and the inflammatory type consisting of papules, pustules, nodules, cysts and scars.
 - pathogenesis of inflammatory acne relates to blockage of the hair follicle with keratin and sebaceous secretions, which are acted upon by Propionibacterium acnes (anaerobe) that causes the release of irritating fatty acids resulting in an inflammatory response.
 - pathogenesis of the obstructive type (comedones) is related to plugging of the outlet of a hair follicle by keratin debris.
 - chocolate, shellfish, nuts iodized salt do not aggravate acne.
 - obstructive type is best treated with benzoyl peroxide and triretnoin (vitamin A acid)
 - treatment of inflammatory type is the above plus antibiotics (topical and/or systemic; erythromycin, tetracycline, clindamycin).

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 

Paget Disease (Osteitis Deformans) 

This unique bone disease is characterized by repetitive episodes of exaggerated, regional osteoclastic activity (osteolytic stage), followed by exuberant bone formation (mixed osteoclastic-osteoblastic stage), and finally by exhaustion of cellular activity (osteosclerotic stage). The net effect of this process is a gain in bone mass; however, the newly formed bone is disordered and lacks strength. Paget disease usually does not occur until mid-adulthood but becomes progressively more common thereafter. The pathognomonic histologic feature is a mosaic pattern of lamellar bone (likened to a jigsaw puzzle) due to prominent cement lines that haphazardly fuse units of lamellar bone. (Fig. 12-5) The axial skeleton and proximal femur are involved in the majority of cases. In patients with extensive disease, hypervascularity of the marrow spaces can result in high-output congestive heart failure. Cranial nerves impingement also occurs and can lead to head ache and auditory disturbances. Rarely Paget disease is complicated by bone sarcoma (usually osteogenic). 

Emphysema

Emphysema is a chronic lung disease. It is often caused by exposure to toxic chemicals or long-term exposure to tobacco smoke.

Signs and symptoms

loss of elasticity of the lung tissue

destruction of structures supporting the alveoli

destruction of capillaries feeding the alveoli

The result is that the small airways collapse during expiration, leading to an obstructive form of lung disease

Features are: shortness of breath on exertion

 hyperventilation and an expanded chest.

As emphysema progresses, clubbing of the fingers may be observed, a feature of longstanding hypoxia.

Emphysema patients are sometimes referred to as "pink puffers". This is because emphysema sufferers may hyperventilate to maintain adequate blood oxygen levels. Hyperventilation explains why emphysema patients do not appear cyanotic as chronic bronchitis (another COPD disorder) sufferers often do; hence they are "pink" puffers (adequate oxygen levels in the blood) and not "blue" bloaters (cyanosis; inadequate oxygen in the blood).

Diagnosis

spirometry (lung function testing), including diffusion testing

X-rays,  high resolution spiral chest CT-scan,

Bronchoscopy, blood tests, pulse oximetry and arterial blood gas sampling.

Pathophysiology :

Permanent destructive enlargement of the airspaces distal to the terminal bronchioles without obvious fibrosis

Oxygen is inhaled in normal breathing

When toxins such as smoke are breathed into the lungs, the particles are trapped by the hairs and cannot be exhaled, leading to a localised inflammatory response. Chemicals released during the inflammatory response (trypsin, elastase, etc.) are released and begin breaking down the walls of alveoli. This leads to fewer but larger alveoli, with a decreased surface area and a decreased ability to take up oxygen and loose carbon dioxide. The activity of another molecule called alpha 1-antitrypsin normally neutralizes the destructive action of one of these damaging molecules.

After a prolonged period, hyperventilation becomes inadequate to maintain high enough oxygen levels in the blood, and the body compensates by vasoconstricting appropriate vessels. This leads to pulmonary hypertension. This leads to enlargement and increased strain on the right side of the heart, which in turn leads to peripheral edema (swelling of the peripherals) as blood gets backed up in the systemic circulation, causing fluid to leave the circulatory system and accumulate in the tissues.

Emphysema occurs in a higher proportion in patient with decreased alpha 1-antitrypsin (A1AT) levels

Prognosis and treatment

Emphysema is an irreversible degenerative condition

Supportive  treatmentis by supporting the breathing with anticholinergics, bronchodilators and (inhaled or oral) steroid medication, and supplemental oxygen as required

Lung volume reduction surgery (LVRS) can improve the quality of life for only  selected patients.

Salivary gland pathology

Inflammation 

a. Sialolithiasis produces a secondary inflammatory reaction  to obstruction and the resultant enlargement of ducts by stones. It may be complicated by actual infection with mouth flora. 

b. Sialadenitis is a primary inflammatory reaction, but it is not always infectious. It may be part of an autoimmune disease  (e.g., Sjogren's syndrome), or the result of bacterial or virals (e.g., mumps) infection. 

Sjögren’s syndrome

a. An autoimmune disease of the salivary and lacrimal glands.
b. Autonuclear antibodies (ANAs) against salivary ducts may be seen.
c. Triad of symptoms include:
(1) Xerostomia—from decreased saliva production.
(2) Keratoconjunctivitis sicca (dry eyes)—from decreased tear production.
(3) Rheumatoid arthritis.
(4) Enlargement of the salivary or lacrimal glands, known as Mikulicz syndrome, may also be observed. 

d. Histologically, a dense infiltration of the gland by lymphocytes is observed.

Tumors

The parotid gland accounts for more than three-quarters of these tumors, most of which are benign. Of the remainder, more occur in the submandibular gland than in the sublingual, and most of these are malignant. Many are surgically, cured, but local recurrence is common. 

a. Pleomorphic adenoma is generally benign and accounts for approximately three-quarters of all salivary gland tumors. If  is composed of multiple epithelial and mesenchymal cell types. Complications may arise due to involvement of cranial nerve VII. 

(a) The most common salivary gland tumor.
(b) Is benign.
(c) Prognosis is good after proper surgical excision.

b. Warthin's tumor (adenolymphoma) is also benign, occuring almost exclusively in the parotid gland. It is grossly cystic.

Microscopic examination reveals cell types suggestive of branchial cleft origin embedded in a lymphoid matrix. 

c. Mucoepidermoid tumors also occur primarily in the parotid and have a high rate of malignant transformation.The malignant component is usually squamous cell.  Prognosis of tumor depends on grade and stage of disease.

d. Cylindroma (adenoid cysticc. Mucoepidermoid tumors carcinoma) is more common in the minor salivary glands found in the oral mucosa, and metastases are more common than in other tumors of the salivary glands. Facial nerve complications are frequent. 
(1) Grossly, the tumor forms multiple lobules surrounded by a capsule. 
(2) Microscopically, small cells form glands containin mucoid material