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Showing posts with the label Internal medicine

Emphysematous pyelonephritis - Review

  DEFINITION  Emphysematous pyelonephritis is an acute necrotizing infection characterized by gas formation. It is characterized by the presence of gas in and around the kidney.   ETIOLOGY   E. coli (58%) and K. pneumoniae (21%) are the organisms most commonly isolated. Clostridium and Enterobacter spp may also be responsible, 7% each.   RISK FACTORS   1) Diabetes mellitus (70-90%)- usually patients with poor glucose control. High levels of glucose in the urine serve as a substrate for these bacteria and large amounts of gas are generated through natural fermentation 2) Obstruction (25-40%)- it is another common predisposing factor for emphysematous pyelonephritis. For non-diabetics, protein fermentation is a proposed source of gas formation.  CLINICAL FEATURES  7% of cases may be asymptomatic. If symptomatic, patients may complain of pneumaturia, irritative lower tract voiding symptoms, flank pain or may present in a severe septic condition with an acute abdomen and hig

BMI versus waist to hip ratio

 DEFINITION  Obesity is a state of excess adipose tissue mass. It is often viewed as equivalent to an increased body weight. This is not true because muscular individuals may have increased body weight but are not obese. Weight follows a continuous distribution pattern in human population. The point at which mortality and morbidity becomes statistically significant is the cut-off to call a patient obese.  METHODS  Various methods have been used to measure obesity. These include: 1) Anthropometry (skin-fold thickness) 2) Densitometry (underwater weighing) 3) CT/MRI 4) Electrical impedance. Still the most common techniques used in clinical practice are: 1) BMI measurement 2) Waist-to-hip ratio measurement.  BMI  It is not an accurate measure of obesity but since it is simple to calculate, it is the most frequently measured parameter. At similar BMI, women usually have more fat than men. When the BMI > 25 Kg/m2, morbidity starts to increase and if associated with ris

Alcoholic liver disease

 INTRODUCTION  Chronic and excessive use of alcohol is one of the major causes of liver disease. 90% of daily heavy drinkers (>60 g alcohol/day) as well as binge drinkers have fatty liver but a smaller percentage (10-35%) of drinkers progress to alcoholic hepatitis which is a precursor for cirrhosis. The long-term risk is 9 times higher in patients with alcoholic hepatitis compared to those with fatty liver alone. Some population-based surveys have documented that men must drink 40 to 80 g of alcohol daily and women must drink 20 to 40 g daily for 10 to 12 years to achieve a significant risk of liver disease. Liver pathology consists of  3 major lesions  that are progressive and rarely exist in a pure form: 1) fatty liver (usually reverses quickly with abstinence), 2) alcoholic hepatitis and 3) cirrhosis. Prognosis of severe alcoholic liver disease (ALD) is bad. Mortality of patients with alcoholic hepatitis concurrent with cirrhosis id nearly 60% at 4 years. Alt


Introduction: Homocysteine is a sulphur containing amino acid that is produced during the conversion of methionine to cysteine. Hyperhomocysteinemia results when there is an abnormality in the homocysteine metabolism. It is an independent risk factor for stroke, MI, peripheral arterial disease and venous thrombotic disease. Even mild to moderate hyperhomocysteinemia is a significant risk factor for vascular disease. Pathophysiology: The amino acid homocysteine is normally metabolized via the transsulfuration pathway by the enzyme cystathionine-β-synthase (CBS), which requires vitamin B6 as co-factor and via the remethylation pathway by the enzymes methylenetetrahydrofolate reductase (MTHFR), which is folate dependent and methionine synthase, which requires vitamin B12 as co-factor. 1 - Methylenetetrahydrofolate reductase 2 - Methionine synthase Hyperhomocysteinemia can be either: 1) Inherited or 2) Acquired. Inherited Inherited severe hyperhomocyste

kussmaul breathing pattern - description and causes

This type of breathing pattern was first described by Adolph Kussmaul, a german physician in 1874. He noticed that his patients with diabetic ketoacidosis had a pattern of breathing which he first labelled as having "air hunger". In the Kussmaul type of breathing, the patient is breathing heavily i.e hyperventilating along with tachypnea. So we will find that the amplitude of the breaths along with the rate will be increased. There is usually no pauses between the breaths. This is not specific for diabetic ketoacidosis. It can also appear in other types of severe metabolic acidoses e.g alcoholic ketoacidosis .

Diaxozide - mechanism of action

The diagram shows a beta cell of the islet of pancreas and will explain how local factors regulate secretion of insulin from it. Glucose enters the cell via the GLUT-2 transporter. Inside the cell there is metabolism with the generation of ATP. This causes the ATP-sensitive K+ channel to close, as shown in A. Closure of this channel leads to cell membrane depolarization. This in turn allows calcium ions to enter the cell via another calcium channel, shown in B. Increased intracellular calcium activates calcium dependent phospholipid protein kinase. This leads to exocytosis of insulin granules. Diaxozide acts by opening the K+ channel. This leads to loss of K+ and causing membrane hyperpolarization. This prevents Ca2+ from entering, protein kinases are not activated and thus there is no exocytosis of insulin granules... 

Prognostic scores in alcoholic hepatitis

1. Maddrey (modified) Discriminant Function score of greater or equal to 32 indicates a high risk (30-50%) risk of mortality at 30 days. The risk is even higher is there are signs of hepatic encephalopathy. Scores should be repeated at day 7. 2. MELD stands for Model for End stage Liver Disease. It is used to estimate 90 days mortality. Poor prognosis if score is greater than 18. Score should be repeated at day 7.

Effect of weather on COPD

Exacerbations of COPD are more commonly seen during the winter season (nearly 1.6 times more frequently). The main cause of these exacerbations is infection with the respiratory virus, rhinovirus. Frequent exacerbations have been shown to lead to a faster decline in the lung function, poorer quality of life and increased mortality. A recent study showed that COPD exacerbations in colder periods of the year take longer to recover from and are more likely to involve cough or coryzal symptoms. The exacerbations in the cold seasons also have a greater impact on daily activity, with patients spending more time indoors and being more likely to be hospitalized with respiratory viral infection.

Diabetes management during ramadan

Diabetes - 7 keys messages to the patients

1. Diabetes is self-managed. Caring for diabetes is more than just taking a daily pill or doing your insulin injection. It may feel like a burden but the decisions you make about physical activity, what and when you will eat will affect both how you feel today and your future health and well-being. 2. Take diabetes seriously. It is a multi-systemic disorder and indeed needs a lot of care. Since the symptoms and complications take time to appear you may think that it is a simple disease but it is not in reality!!! 3. Learn everything about the disease. Since most of diabetes care is  about self-care, the more you know about it, the better you will be able to manage it. You can control your diabetes rather than letting your diabetes control you. If possible, try to get updated with latest developments in the field and read to drive away myths about the disease. 4. Your treatment will change over time. Treatment of diabetes will eventually change over time. Changes in treatm

Mediterranean diet and cognitive decline

A Mediterranean diet is one which comprises of fresh vegetables, fruits, beans, whole grains, nuts, olives, and olive oil along with some cheese, yogurt, fish, poultry, eggs, and wine. A recent study has shown that this diet if adopted and followed leads to a slower decline in the cognitive function. The two main hypotheses are that it has a lot of anti-oxidants which prevent cell death in the brain and secondly it has a protective effect on the vasculature of the brain and thus prevents vascular dementia. Thus, the Mediterranean diet not only improve your looks and protects your cardiovascular system but also your brain cells benefit from it.

Highest prevalence of Diabetes Mellitus

Figures till November 2012 show that the top 5 countries with the highest prevalence of Diabetes Mellitus are from the pacific islands. They may be the smallest islands but the epidemic of diabetes is one of the worst there. More than a third of adults in some of these countries have diabetes and the combined toll of complications, deaths and loss of income make diabetes a real threat not just to the individuals experiencing the disease but also to the economies of the countries themselves. Above is an image showing the locations of the pacific islands.

Top 10 countries with Diabetes Mellitus 2012

Data till November 2012 showed that together, these 10 countries make up 75% of the total prevalence of diabetes in the world.  Urbanisation and the accompanying changes in lifestyle are the main drivers of the epidemic in addition to changes in population structure where more people are living longer.

Anemia in diabetic patients - Erythropoietin treatment?

If you encounter a normochromic and normocytic anemia in a diabetic patient, do not forget that it may be a case of erythropoietin deficiency. This deficiency can occur early in diabetic nephropathy (well before stage 5 of chronic kidney disease). In adults, about 85-90% of the erythropoietin comes from the kidneys and 10-15% from the liver. It is produced by interstitial cells in the peritubular capillary bed of the kidneys and by perivenous hepatocytes in the liver. In cases of decreased renal mass, the level of erythropoietin falls and does not increase much in response to hypoxia (anemia). This occurs even if the liver is normal as the latter cannot compensate for the kidney's loss of function. Since the availability of recombinant human erythropoietin to patients in 1989, anemia and transfusion requirements have become relatively  rare in patients on hemodialysis. After adequate treatment with erythropoietin, studies have demonstrated that there is an: 1) enhanced exerci

Acanthosis nigricans - cause and significance

Acanthosis nigricans is a hyperpigmented velvety lesion usually found in the neck and the axillary region. It can also be seen elsewhere e.g. the belt line, creases over the dorsal surface of fingers. The palms and soles are typically not involved. Pathologically, it is characterized by an increased number of melanocytes associated with hyperkeratotic epidermal papillomatosis. It is strongly associated with insulin resistance but it is a non-specific condition and can also be found in obesity, polycystic ovarian syndrome, endocrine diseases like acromegaly and Cushing's syndrome, as well as some malignant tumours. The severity of the acanthosis nigricans correlates with the degree of insulin resistance and the level of serum insulin. The exact mechanism of its formation is still unclear but it is speculated that there are related IGF-1 receptors in the skin which are activated by ambient hyperinsulinemia. If the insulting factor is removed, there may be a regression of the

Classification of Diabetes Mellitus

Diabetes is divided into 4 different classes: 1) Type 1 diabetes (results from beta-cell destruction, usually leading to absolute insulin deficiency) 2) Type 2 diabetes (results from a progressive insulin secretory defect on the background of insulin resistance) 3) Other specific types of diabetes due to other causes, e.g. genetic defects in beta-cell function, genetic defects in insulin action, diseases of the exocrine pancreas (such as cystic fibrosis, pancreatitis) and drug- or chemical-induced (such as in the treatment of HIV/AIDS or after organ transplantation) 4) Gestational diabetes mellitus (GDM) (diabetes diagnosed for the first time during pregnancy that is not clearly overt diabetes).

Respiratory failure - Definition, classification and difference between acute and chronic type

Respiratory failure may be classified as hypercapnic or hypoxemic. Hypercapnic respiratory failure is defined as an arterial PCO2 (PaCO2 ) greater than 45mmHg. Hypoxemic respiratory failure is defined as an arterial PO2 (PaO2 ) less than 55 mmHg when the fraction of oxygen in inspired air (FiO2) is 0.60 or greater. In many cases, hypercapnic and hypoxemic respiratory failure coexist. Distinctions between acute and chronic respiratory failure are summarized in the table below. In general, acute hypercapnic respiratory failure is defined as a PaCO2 greater than 45 mmHg with accompanying acidemia (pH less than 7.30). The physiological effect of a sudden increase in PaCO2 depends on the prevailing level of serum bicarbonate anion. In patients with chronic hypercapnic respiratory failure e.g. COPD, a long-standing increase in PaCO2 results in renal compensation and an increased serum bicarbonate concentration. A superimposed acute increase in PaCO2 has a less dramatic effect th

May-Thurner syndrome

As seen in the diagram above, the left common iliac vein is predisposed to be compressed by the right common iliac artery. This can lead to stasis and eventually causing thrombosis. Another effect is that the pulsatile nature of the artery over the vein leads to turbulence in the blood flow, thereby favouring thrombosis.  Because of this anatomical predisposition, most Deep Vein Thrombosis (DVT) seen during pregnancy occur in the left iliac vein system. All the classic investigations done for cases of DVT should be performed here also.

Barrel shaped chest

Barrel shaped chest is commonly encountered in the clinical setting. It is seen in emphysema, hence also called as emphysematous chest. The anteroposterior diameter is increased (normally transverse:AP diameter is 7:5). The subcostal angle is wide (usually it is acute at around 70 degrees). The angle of Louis is unduly prominent with the sternum more arched. The spine is concave forwards and the ribs are less oblique. The respiratory movements are diminished bilaterally, with the mediastinum remaining in the central position. On percussion, the lung is hyper-resonant. On auscultation, there is a diminished vesicular breathing with a prolonged expiration. Rhonchi may be present.

Body Mass Index - BMI

Body Mass Index is also known as the Quetelet Index, after the Belgian astronomer, statistician, sociologist and mathematician Lambert Adolphe Jacques Quetelet. It is a very easy and frequently used method to assess obesity, though it is not a direct measure of adiposity. It is c alcula ted by dividing the patient body mass (kg) by the square of his/her height (m). BMI = kg/ m 2 Classification of weight status: BMI (kg/m 2 ) Obesity Class Risk of Disease Underweight < 18.5 Healthy weight 18.5–24.9 Overweight 25.0–29.9 Increased Obesity 30.0–34.9 I High Obesity 35.0–39.9 II Very high Extreme Obesity > 40 III Extremely high Obesity is defined as a BMI varying from 30-39.9 kg/ m 2 . It is further classified into grades I, II and III. Extreme obesity with a BMI of greater than 40 is also called as morbid obesity. As seen on the right side of the table above, being overweight and the various classes of obesity is closely related t