THE PITUITARY GLAND 

This is a small, bean-shaped structure that lies at the base of the brain within the confines of the sella turcica. It is connected to the hypothalamus by a "stalk," composed of axons extending from the hypothalamus. The  pituitary is composed of two morphologically and functionally distinct components: the anterior lobe (adenohypophysis) and the posterior lobe (neurohypophysis). The adenohypophysis, in H&E stained sections, shows a colorful collection of cells with basophilic, eosinophilic or poorly staining ("chromophobic") cytoplasm.

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.

Systemic Candidiasis (Candidosis; Moniliasis)

Invasive infections caused by Candida sp, most often C. albicans, manifested by fungemia, endocarditis, meningitis, and/or focal lesions in liver, spleen, kidneys, bone, skin, and subcutaneous or other tissues.

Infections due to Candida sp account for about 80% of all major systemic fungal infections.

Symptoms and Signs

Esophagitis is most often manifested by dysphagia. Symptoms of respiratory tract infections are nonspecific, such as cough. Vaginal infections cause itching, burning, and discharge. Candidemia usually causes fever, but other symptoms are typically nonspecific. Sometimes, a syndrome develops resembling bacterial sepsis, with a fulminating course that may include shock, oliguria, renal shutdown, and disseminated intravascular coagulation.

Hematogenous endophthalmitis starts as white retinal plaques that can cause blindness as destructive inflammation progresses, extending to opacify the vitreous and causing potentially irreversible scarring. Most often, there are no symptoms in early stages of Candida endophthalmitis. If treatment is not begun before symptoms appear, significant or even total loss of vision is likely to occur in the affected eye. In neutropenic patients, eye involvement is more often manifested by retinal hemorrhages; papulonodular, erythematous, and vasculitic skin lesions may also develop.

Pulmonary embolism

A pulmonary embolism (thromboembolism) occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes to the arterial blood supply of one of the lungs.

Clinical presentation

Signs of PE are sudden-onset dyspnea (shortness of breath, 73%), tachypnea (rapid breathing, 70%), chest pain of "pleuritic" nature (worsened by breathing, 66%), cough (37%), hemoptysis (coughing up blood, 13%), and in severe cases, cyanosis, tachycardia (rapid heart rate), hypotension, shock, loss of consciousness, and death. Although most cases have no clinical evidence of deep venous thrombosis in the legs, findings that indicate this may aid in the diagnosis.

Diagnosis

The gold standard for diagnosing pulmonary embolism (PE) is pulmonary angiography

An electrocardiogram may show signs of right heart strain or acute cor pulmonale in cases of large PEs

In massive PE, dysfunction of the right side of the heart can be seen on echocardiography, an indication that the pulmonary artery is severely obstructed and the heart is unable to match the pressure.

Treatment

Acutely, supportive treatments, such as oxygen or analgesia

In most cases, anticoagulant therapy is the mainstay of treatment. Heparin or low molecular weight heparins are administered initially, while warfarin therapy is given

Asthma

Asthma is

(1) An obstructive lung disease characterized by narrowing of the airways.

Inflammation of the airways is a major component of asthma.

(2) Common symptoms are dyspnea, wheezing on expiration, and coughing.

(3) Two types:

(a) Extrinsic (allergic, atopic) asthma

(i) An atopic allergy caused by a type I immediate hypersensitivity immune reaction to an allergen.

(ii) Seen in children, adults.

(b) Intrinsic (nonallergic) asthma

(i) Not caused by an allergic reaction.

(ii) Mostly seen in adults.

The disorder is a chronic inflammatory condition in which the airways develop increased responsiveness to various stimuli, characterized by bronchial hyper-responsiveness, inflammation, increased mucus production, and intermittent airway obstruction.

Signs and symptoms

• The clinical hallmarks of an attack are shortness of breath (dyspnea) and wheezing
• A cough—sometimes producing clear sputum—may also be present
• The onset is often sudden; there is a "sense of constriction" in the chest, breathing becomes difficult, and wheezing occurs
• Signs of an asthmatic episode are wheezing, rapid breathing (tachypnea), prolonged expiration, a rapid heart rate (tachycardia), rhonchous lung sounds (audible through a stethoscope), and over-inflation of the chest.
• During very severe attacks asthma sufferer can turn blue due to lack of oxygen , can experience chest pain or even loss of consciousness, may lead to respiratory arrest and death

Pathophysiology

Bronchoconstriction : asthma is the result of an abnormal immune response in the bronchial airways. The airways of asthmatics are "hypersensitive" to certain triggers, also known as stimuli, these stimuli include allergens, medications , air pollution, early child hood infection, exercise, emotional stress

Bronchial inflammation asthma resulting from an immune response to inhaled allergens—are the best understood of the causal factors. In both asthmatics and non-asthmatics, inhaled allergens that find their way to the inner airways are ingested by a type of cell known as antigen presenting cells These activate an humoral immune response. The humoral immune system produces antibodies against the inhaled allergen. Later, when an asthmatic inhales the same allergen, these antibodies "recognize" it and activate a humoral response. Inflammation results: chemicals are produced that cause the airways to constrict and release more mucus, and the cell-mediated arm of the immune system is activated. The inflammatory response is responsible for the clinical manifestations of an asthma attack

Symptomatic Treatment

Episodes of wheeze and shortness of breath generally respond to inhaled  bronchodilators which work by relaxing the smooth muscle in the walls of the bronchi., More severe episodes may need short courses of inhaled, oral, or intravenous steroids which suppress  inflammation and reduce the swelling of the lining of the airway.

Bronchodilators (usually inhaled)

Short-acting selective  beta2-adrenoceptor agonists(salbutamol, terbutaline)

less selective adrenergic agonists, such as inhaled epinephrine and ephedrine tablets

Antimuscarinics

Systemic steroids

Oxygen to alleviate the hypoxia that is the result of extreme asthma attacks.

If chronic acid indigestion ( GERD) is part of the attack, it is necessary to treat it as well or it will restart the inflammatory process

Preventive Treatment

most effective preventive medication are

Inhaled  corticosteroids

Long-acting beta2-adrenoceptor agonists

Leukotriene modifiers

Mast cell stabilizers

Methylxanthines (theophylline and aminophylline),

Antihistamines, often used to treat allergic symptoms

Streptococcal pharyngitis:

A disease of young people, enlarged lymphoid nodules and keratin plugs in the tonsillar pits is seen Complications include retro-pharyngeal abscess (quinsy)

Cellulitis of the deep tissues of the neck is Ludwig's angina

Scarlet fever ("scarlatina") is a strep throat caused by a streptococcus with the gene to make one of the erythrogenic toxins, Patients have a rash with PMNs

Streptococcal skin infections (Impetigo)

Erysipelas is a severe skin infection caused by group A strep; geographic of red, thickened, indurated areas of the skin are characteristic. Unlike staph infections, there is usually little or no tissue necrosis

Post-streptococcal hypersensitivity diseases include rheumatic fever, post-streptococcal glomerulonephritis, and some cases of erythema nodosum