Causes of Atrial Fibrillation

In this article, we will discuss various Causes of Atrial Fibrillation. So, let’s get started.

It is characterized by rapid atrial rate >350 beats/min, uncoordinated atrial contractions and irregular rapid ventricular response. It is a common supraventricular arrhythmia which may occur in paroxysms (paroxysmal atrial fibrillation) and persistent forms (chronic atrial fibrillation). Following are the various causes of atrial fibrillation.


Rheumatic Heart Disease (Mitral Stenosis, Mitral Regurgitation, etc)

Mitral valve prolapse

Hypertensive heart disease

Cardiomyopathy, alcohol induced (holiday heart syndrome)


Congenital heart disease (ASD, Ebstein’s anomaly)

Constrictive pericarditis

Cor pulmonale

Left atrial myxoma

Idiopathic (lone atrial fibrillation)


Pathogenesis of Thrombotic Thrombocytopenic Purpura

In this article, we will discuss the Pathogenesis of Thrombotic Thrombocytopenic Purpura. So, let’s get started.


The pathogenesis of thrombotic thrombocytopenic purpura (idiopathic or inherited) is related to deficiency of, or antibodies to, a metalloprotease that cleaves vWF and ADAMTS 13 respectively. Non-cleavage of large vWF molecules results in their persistence which leads to platelet aggregation and adhesion. The manifestations are as a result of localized platelet thrombi and fibrin deposition in microvasculature. Arterioles are filled with hyaline material (fibrin and platelets) and similar material may also be seen beneath the endothelium of the involved vessels. Immunofluorescence studies have shown deposition of immunoglobulins and complement in arterioles indicating an immunologic origin. Microaneurysm of arterioles may also be seen.

Signs and Symptoms of Adrenal Insufficiency

In this article, we will discuss various Signs and Symptoms of Adrenal Insufficiency. So, let’s get started.

Signs and Symptoms

Glucocorticoid deficiency

  • Weight loss, weakness, lack of energy, fatigue
  • Anorexia, nausea, vomiting
  • Diarrhea or constipation
  • Postural hypotension, syncope, shock
  • Joint pain, myalgia
  • Hypoglycemia, hyponatremia, and hypercalcemia
  • Anemia, lymphocytosis, eosinophilia

Mineralocorticoid insufficiency

  • Postural hypotension
  • Shock
  • Hyponatremia
  • Salt craving and abdominal pain
  • Hyperkalemia

ACTH excess

  • Pigmentation on sun-exposed areas, pressure sores, e.g. elbow, knee and mucous membrane, conjunctivae, palmar creases, and recent scars

Adrenal androgen insufficiency

  • Decreased body hair (e.g. pubic, axillary) and loss of libido especially in females
  • Lack of energy
  • Dry and itchy skin

Predisposing Factors or Conditions for Bacterial Meningitis

In this article, we will discuss various Predisposing Factors or Conditions for Bacterial Meningitis. So, let’s get started.

Acute meningitis is an inflammatory response to the infection of leptomeninges (pia-arachnoid matter) with exudation of the cerebrospinal fluid (CSF) in the subarachnoid space. Acute meningitis can be bacterial (septic, tubercular or pyogenic), viral or fungal, etc. Following are the predisposing factors or condition for Bacterial Meningitis:

Factors or Conditions

  • Pneumonia
  • Otitis media, Sinusitis or Mastoiditis
  • Bacterial endocarditis
  • Splenectomy or asplenic state
  • Old age
  • Hypogammaglobulinemia
  • Alcoholism, Diabetes
  • Immunocompromised state
  • Cirrhosis of liver
  • Multiple myeloma
  • Head trauma with a basilar skull fracture and CSF rhinorrhea

Penrose and T- Tube Drain

In this article, we will discuss the Penrose and T-tube Drain. So, let’s get started.

Penrose Drain

It consists of a soft rubber tube placed in a wound area to prevent the build-up of fluid. It is named after the American gynecologist Charles Bingham Penrose. A Penrose drain removes fluid from a wound area. It can also be used to drain cerebrospinal fluid to treat hydrocephalus patients. The Penrose drain is a common passive drain.

  • Material: Latex rubber, silicone
  • Sizes: 1/4×6, 1/2×6, 3/4×6, 1×6 inches

T-tube Drain

It is used mostly for patients who have undergone gallbladder surgery or surgery of the surrounding tubes draining the gall bladder. It is placed in the common bile duct post common bile duct exploration (CBD exploration) with supraduodenal choledochotomy. It provides external drainage of bile in a controlled route while the healing process of choledochotomy is maturing and the original pathology is resolving. This type of drainage resembles T shape hence the name T-tube drain. The collection finally drains into a collection bag.