Skip to main content


Showing posts from July, 2012

Diabetes Mellitus - Definition / Criteria for diagnosis

Definition: It is a group of metabolic disorders that is characterized by hyperglycemia which is due to a relative or absolute deficiency in insulin. There is usually a defect in insulin secretion, a defect in insulin action or a combination of both.  Criteria for diagnosis: 1) An Fasting Plasma Glucose   ≥  7.0 mmol/L (126 mg/dL),  2) A Plasma Glucose    ≥  11.1 mmol/L (200 mg/dL) 2 h after an oral glucose tolerance test, 3) An HbA1c    ≥    6.5% or 4) A Random Plasma Glucose concentration    ≥   11.1 mmol/L (200 mg/dL) accompanied by classic symptoms of DM (polyuria, polydipsia, polyphagia, weight loss).  Note: 1) Fasting means no calorie intake for the past 8 hours. 2) For the glucose tolerance test, we must use 75 g of anhydrous glucose dissolved in water. 3) The diagnostic HbA1c test should be performed using a method certified by the National Glycohemoglobin Standardization Program (NGSP) and standardized or traceable to the Diabetes Control and Complications Trial (D

Chronic Obstructive Pulmonary disease - Definition

COPD is a preventable and treatable systemic disease state characterized by a progressive airflow limitation that is not fully reversible and associated with an abnormal inflammatory response of the lungs to noxious particles and gas. Note that the new definition according to GOLD/ATS and ERS does not talk anything about the disease being a mixture of chronic bronchitis and emphysema, though these conditions are very frequently encountered in COPD and also the fact of being 'not fully reversible' distinguishes this disease from the other chronic obstructive condition which is bronchial asthma.

Ice water test - Traumatic spinal cord injury

This test was first described by Bors and Blinn in 1957. The authors did this test to check if there are any temperature receptors in the bladder, how they work and whether the test can have a diagnostic purpose. Procedure: (originally done by Bors and Blinn) 60 mL of ice cold water is instilled in the bladder in 30 seconds and patient is requested to try to retain the fluid. Results: If water is expelled in less than 1 minute, the test is said to be positive. Interpretation: The rapid evacuation of the fluid is due to the reflex contraction of the detrusor muscle. The authors also found that this test was positive in patients having an upper motor neuron lesion. The physiology behind is that there are cold receptors in the bladder wall. From there, the impulses travel through the afferent C fibers to the spinal cord and return via the motor nerves to the detrusor muscle thereby completing the reflex arc. This reflex is normally present in children up to the age of 4. After

Centriacinar / Centrilobular emphysema

In a classical lesion, dilated and destroyed respiratory bronchioles coalesce in series and in parallel to produce sharply demarcated emphysematous spaces. They are separated from the acinar periphery (the  lobular septa) by intact  alveolar ducts and sacs of normal size, as shown by the diagram below.  The lesions vary in quality and quantity even within the same lung. There is striking irregularity of involvement of lobules, and even within the same lobule. The lesions are usually more common and become more severe in the upper than in the lower zones of the lung. Most affected are the upper lobe, particularly the posterior and apical segments, and the superior segment of the lower lobe as depicted below.  This type of emphysema is commonly seen in chronic cigarette smokers. For classification of emphysema, follow this link:  Emphysema