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Hyperhomocysteinemia

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 .

Adverse effects of Amiodarone

1) Hypotension can occur especially with the intravenous form due to vasodilation and depressed myocardial performance. Long-term oral therapy can also cause depressed contractility but it is unusual. 2) Nausea can sometimes be seen during the loading phase. All we have to do is to decrease the daily dose of the medication. 3) Pulmonary fibrosis is the most serious adverse effect during chronic amiodarone therapy. The fibrosis can be rapidly progressive and fatal. The risk factors include: underlying lung disease, doses of 400 mg/day or more and recent pulmonary insults such as pneumonia. Early amiodarone toxicity can be detected using pulmonary function tests and serial chest X-rays. 4) Other adverse effects that may be seen during long-term therapy include a) corneal microdeposits (which often are asymptomatic), b) hepatic dysfunction, c) vivid and disturbing dreams d) neuromuscular symptoms (most commonly peripheral neuropathy or proximal muscle weakness), e) photosensitiv

Aminoglycosides - why -mycin and -micin

The aminoglycoside group includes gentamicin, amikacin, netilmicin, kanamycin, tobramycin, streptomycin, paromomycin and neomycin. These drugs have a good action against aerobic gram-negative bacteria. They are rapidly bactericidal. Bacterial killing is concentration dependent: The higher the concentration, the greater is the rate at which bacteria are killed. As noted above, some of the names end by -micin while others by -mycin. The reason behind this lies in the origin of the antibiotics. All the antibiotics ending with -mycin are either natural products or semisynthetic derivatives of compounds produced by a variety of soil actinomycetes notably Streptomyces . Those ending with -micin are derived from other actinomycetes e.g Micromonospora.

Atrial septal defect device closure

This procedure is called as Atrial septal defect (ASD) device closure. Transesophageal echocardiography (TEE) is must before procedure for: 1) actual sizing of the defect 2) defining the rims - to hold device in place 3) ruling out anomalous pulmonary venous drainage 4) ruling out significant mitral regurgitation (MR). Intraprocedural TEE is not mandatory. N.B How to distinguish between an ASD device and a patent foramen ovale (PFO) device? Left atrial (LA) disk (green arrow) is larger than Right atrial (RA) disk (yellow arrow), thus it is an ASD device.For a PFO device, RA disk will be larger than LA disk. Further readings:

A case of Mycobacterium marinum infection in a fisherman

Historically recognized as “swimming pool” or “fish tank” granuloma. Clinical features: Most infections occur 2 to 3 weeks after contact with contaminated water from one of these sources. The lesions are most often small violet papules on the hands and arms that may progress to shallow, crusty ulcerations and scar formation. Lesions are usually singular. However, multiple ascending lesions resembling sporotrichosis can occasionally occur. Most patients are clinically healthy with a previous local hand injury that becomes infected while cleaning a fish tank or patients may sustain scratches or puncture wounds from saltwater fish, shrimp, fins and other marine life contaminated with M. marinum. Swimming pools seem to be a risk only when non-chlorinated. Diagnosis: Diagnosis is made from culture and histologic examination of biopsy material, along with a compatible history of exposure. Treatment: No treatment of choice is recognized for M. marinum. However, successful treatmen

COPD exacerbation - definition, assessment, management

COPD exacerbation: Definition: Exacerbation of COPD is defined as an acute episode, characterized by the worsening of the patient’s respiratory symptoms that is beyond normal daily variations and that will eventually lead to a change in his medications. Those having 2 or more exacerbations per year are known as “frequent exacerbators”. Precipitating factors: 1) Respiratory tract infections – viral or bacterial. Most common cause. There may be an increased bacterial burden in the lower airways or new strains of bacteria are acquired during an exacerbation. Commonly implicated viruses include rhinovirus, respiratory syncytial virus, coronavirus and influenza virus. 2) Air pollution. 3) Interruption of maintenance therapy. 4) Unknown causes – 30% cases. Diagnosis: Diagnosis should be made clinically whereby the patient complains of an acute aggravation of his symptoms out of proportion to his day to day variations.  Assessment: Medical history: 1) Se