MBBS question bank

 Bronchial asthma Asthma is a chronic inflammatory disease of the smaller airways, characterised by episodic, reversible bronchial obstruction due to hyper-responsiveness of tracheobronchial tree to a multiplicity of intrinsic and extrinsic stimuli manifested clinically by paroxysms of polyphonic wheeze, dyspnoea, chest tightness and cough which may be relieved spontaneously or as a result of therapy. ASTHMA BRONCHIOLE Types of Asthma Extrinsic Asthma (Atopic Asthma, Early Onset Asthma) Onset is in childhood. It occurs in atopic individuals who readily form IgE antibodies in response to allergens. Atopic patients can be identified by skin sensitivity tests. Intrinsic Asthma (Non-atopic Asthma, Late Onset Asthma) It can be begin at any age, especially in late adulthood. There is no role for allergens in the production of disease. Nocturnal Asthma It is defined as an overnight fall of more than 20% in the FEV1 or PEFR. This is presumed to be due to: Early morning fall in circulating adre

  Mechanism of normal labor Definition: The series of movements that occur on the head in the process of adaptation during its journey through the pelvis is called mechanism of labor. Mechanism:   In normal labor, the head enters the brim more commonly through the available transverse diameter (70%) and to the lesser extent through one of the oblique diameters. The position is either occipitolateral or oblique occipitoanterior. Left occipitoanterior is more common than right occipitoanterior as the left oblique diameter is encroached by the rectum. The engaging anteroposterior diameter of the head is either suboccipitobregmatic 9.5 cm or in slight deflexion-the suboccipitofrontal 10 cm. The engaging transverse diameter is biparietal 9.5 cm. As the occipitolateral position is most common, the mechanism of the labor in such position will be described. The principal movements are: Engagement Descent Flexion Internal rotation  Crowning Extension Restitution External rotation Expulsion of

  Pleural Effusion: Causes, Clinical features, Investigations And Management Pleural effusion is the accumulation of serous fluid in the pleural cavity. Mechanism of Pleural Fluid Formation Elevation of venous pressure (rare in pure Right Ventricular failure) Decreased plasma oncotic pressure (except in congenital hypoalbuminuaemia) Increased capillary permiability due to local inflammation, toxins or vasoactive substances as occurs in collagen-vascular diseases, pancreatitis, pulmonary emboli and pneumonitis Increase in pleural space oncotic pressure as a result of : Protein leak through capillaries, Protein exudation due to local pleural inflammation, Defective lymphatic absorption. Simple transfer of ascitic fluid across diaphragmatic defect and also through transdiaphragmatic lymphatics as occurs in cirrhosis and Meig's syndrome. Increased negativity of pressure in the pleural also results in pleural effusion as occurs in atelectasis. Obstruction of lymphatics. Pleural fluid, o

  Acne vulgaris Acne vulgaris is a disorder of pilosebaceous complex which predominantly affects the peripubertal population and clinically manifests as comedones (open- blackheads, closed- whiteheads), papules, nodules, pustules and cysts and heals with scars. Pathogenesis 1. Occlusion of pilosebaceous orifice Pilosebaceous orifice in acne is occluded by a keratinous plug induced by: chemicals (cosmetics) and reduced levels of linoleic acid in sebum of acne patients. Results in retention of sebum, encouraging growth of microbes, triggering a vicious cycle. Distended follicle ruptures, releasing proinflammatory chemicals into the dermis, stimulating intense inflammation.  Ductal epithelium also produces cytokines and an inflammatory cascade is triggered. 2.  Increased sebum production Sebaceous gland activity is controlled by androgens. Most patients have normal levels of circulating androgens, but their sebaceous glands are unusually sensitive to androgens due to an enhanced end organ