Mesothelioma Update

Malignant mesothelioma is a rare cancer that occurs in the thin layer of tissue that covers the majority of your internal organs (mesothelium). Doctors divide mesothelioma into different categories based on what part of the mesothelium is affected by cancer. Mesothelioma that occurs in the tissue that surrounds the lung (pleura) is called pleural mesothelioma and is the most common form. Mesothelioma that occurs in the tissue in your abdomen (peritoneum) is called peritoneal mesothelioma and accounts for 10 percent to 20 percent of all mesotheliomas. In rare cases, mesothelioma can also occur in the lining around the heart (pericardium) and in the lining around the testicles (tunica vaginalis).

Osteomyelitis

Osteomyelitis is an infection of bone or bone marrow, usually caused by pyogenic bacteria or mycobacteria. It can be usefully subclassifed on the basis of the causative organism, the route, duration and anatomic location of the infection.

Deep Vein Thrombosis (DVT)

Deep-vein thrombosis (also known as deep-venous thrombosis or DVT and colloquially as economy class syndrome) is the formation of a blood clot ("thrombus") in a deep vein. It commonly affects the leg veins, such as the femoral vein or the popliteal vein or the deep veins of the pelvis. Occasionally the veins of the arm are affected (known as Paget-Schrötter disease). Thrombophlebitis is the more general class of pathologies of this kind. There is a significant risk of the thrombus embolizing and traveling to the lungs causing a pulmonary embolism.

Disseminated Intravascular Coagulation

Disseminated intravascular coagulation (DIC), also called consumptive coagulopathy, is a pathological process in the body where the blood starts to coagulate throughout the whole body. This depletes the body of its platelets and coagulation factors, and there is a paradoxically increased risk of hemorrhage. It occurs in critically ill patients, especially those with Gram-negative sepsis (particularly meningococcal sepsis) and acute promyelocytic leukemia.

The treatment of underlying cause is a must and should be initiated immediately. Anticoagulants are only given when indicated (development of thrombotic renal complications) as patients with DIC are prone to bleeding. Platelets may be transfused if counts are very low, and fresh frozen plasma may be administered.
DIC results in lower fibrinogen (as it has all been converted to fibrin), and this can be tested for in the hospital lab. A more specific test is for "fibrin split products" (FSPs) or "fibrin degradation products" (FDPs) which are produced when fibrin undergoes degradation when blood clots are dissolved by fibrinolysis.
In some situations, infusion with antithrombin may be necessary. A new development is drotrecogin alfa, a recombinant activated protein C product. Activated Protein C (APC) deactivates clotting factors V and VIII, and the presumed mechanism of action of drotrecogin is the cessation of the intravascular coagulation. Due to its high cost, it is only used strictly on indication in intensive care patients.
The prognosis for those with DIC, depending on its cause, is often grim, leading the initials to be known colloquially as "death is coming".

Source : Wikipedia

Bronchiectasis

Inrtoduction:

Bronchiectasis is a disease that causes localized, irreversible dilatation of part of the bronchial tree. Involved bronchi are dilated, inflamed, and easily collapsible, resulting in airflow obstruction and impaired clearance of secretions. Bronchiectasis is associated with a wide range of disorders, but it usually results from necrotizing bacterial infections, such as infections caused by the Staphylococcus or Klebsiella species or Bordetella pertussis.

Pathogenesis:
Dilation of the bronchial walls results in airflow obstruction and impaired clearance of secretions because the dilated areas disrupt normal air pressure in the bronchial tubes, causing sputum to pool inside the dilated areas instead of being pushed upward. The pooled sputum provides an environment conducive to the growth of infectious pathogens, and these areas of the lungs are thus very vulnerable to infection. The more infections that the lungs experience, the more damaged the lung tissue and alveoli become. When this happens, the bronchial tubes become more inelastic and dilated, creating a self-perpetuating cycle of further damage to the lungs.

Causes:
There are both congenital and acquired causes of bronchiectasis. Kartagener syndrome, which affects the mobility of cilia in the lungs, aids in the development of the disease. Another common genetic cause is cystic fibrosis, in which a small number of patients develop severe localized bronchiectasis. Young's syndrome, which is clinically similar to cystic fibrosis, is thought to significantly contribute to the development of bronchiectasis. This is due to the occurrence of chronic, sinopulmonary infections. Patients with alpha 1-antitrypsin deficiency have been found to be particularly susceptible to bronchiectasis, for unknown reasons. Other less-common congenital causes include primary immunodeficiencies, due to the weakened or nonexistent immune system response to severe, recurrent infections that commonly affect the lung.

Treatment:
Treatment of bronchiectasis is aimed at controlling infections and bronchial secretions, relieving airway obstruction, and preventing complications. This includes the prolonged usage of antibiotics to prevent detrimental infections, as well as eliminating accumulated fluid with postural drainage and chest physiotherapy. Surgery may also be used to treat localized bronchiectasis, removing obstructions that could cause progression of the disease.
Inhaled steroid therapy that is consistently adhered to can reduce sputum production and decrease airway constriction over a period of time, and help prevent progression of bronchiectasis. One commonly used therapy is beclometasone dipropionate, which also used in asthma treatment. Use of inhalers such as albuterol (salbutamol), fluticasone (Flovent/Flixotide) and ipratropium (Atrovent) may help reduce likelihood of infection by clearing the airways and decreasing inflammation.

Mesothelioma

Mesothelioma is a form of cancer that is almost always caused by previous exposure to asbestos. In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body's internal organs. Its most common site is the pleura (outer lining of the lungs and chest cavity), but it may also occur in the peritoneum (the lining of the abdominal cavity) or the pericardium (a sac that surrounds the heart).

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or have been exposed to asbestos dust and fibre in other ways, such as by washing the clothes of a family member who worked with asbestos, or by home renovation using asbestos cement products. Unlike lung cancer, there is no association between mesothelioma and smoking.

Source : Wikipedia

Bubonic Plague

Source:Wikipedia

Meckel's diverticulum

Introduction:
A Meckel's diverticulum, a true congenital diverticulum, is a small bulge in the small intestine present at birth. It is a vestigial remnant of the omphalomesenteric duct (also called the vitelline duct), and is the most frequent malformation of the gastrointestinal tract. It is present in approximately 2% of the population, with males more frequently experiencing symptoms.

Symptoms:
If symptoms do occur, they typically appear before the age of two.
The most common presenting symptom is painless rectal bleeding, followed by intestinal obstruction, volvulus and intussusception. Occasionally, Meckel's diverticulitis may present with all the features of acute appendicitis. Also, severe pain in the upper abdomen is experienced by the patient along with bloating of the stomach region. At times, the symptoms are so painful such that they may cause sleepless nights with extreme pain in the abdominal area.

Treatment:
Treatment is surgical, consisting of a resection of the affected portion of the bowel.

Whipple's disease

Introduction:
Whipple's disease is a rare, systemic infectious disease caused by the bacterium Tropheryma whipplei. First described by George Hoyt Whipple in 1907 and commonly considered a gastrointestinal disorder, Whipple's disease primarily causes malabsorption but may affect any part of the body including the heart, lungs, brain, joints, and eyes. Weight loss, diarrhea, joint pain, and arthritis are common presenting symptoms, but the presentation can be highly variable.







This micrograph shows the typical findings of enlarged villus with abundant macrophages in the in small intestine.







Symptoms:

• Arthritis or arthralgia
• malabsorption
• intestinal lipodystrophy (accumulation of fatty deposits in lymph nodes of the intestine)
• lymphadenopathy
• abdominal pain
• diarrhea
• fever
• melanoderma
• Neurological symptoms

Treatment:

Treatment is with penicillin, ampicillin, tetracycline or co-trimoxazole for 1 -2 years.

Crohn's Disease

Introduction:
Crohn's disease (also known as regional enteritis) is a chronic, episodic, inflammatory condition of the gastrointestinal tract characterized by transmural inflammation (affecting the entire wall of the involved bowel) and skip lesions (areas of inflammation with areas of normal lining between). Crohn's disease is a type of inflammatory bowel disease (IBD) and can affect any part of the gastrointestinal tract from mouth to anus; as a result, the symptoms of Crohn's disease vary among afflicted individuals. The main gastrointestinal symptoms are abdominal pain, diarrhea (which may be bloody) or constipation, vomiting and weight loss. Crohn's disease can also cause complications outside of the gastrointestinal tract such as skin rashes, arthritis, and inflammation of the eye.



Symptoms:
Gastrointestinal symptoms:
Abdominal pain may be the initial symptom of Crohn's disease. The pain is commonly cramp-like and may be relieved by defecation. It is often accompanied by diarrhea, which may or may not be bloody, though constipation is not uncommon especially in those who have had surgery. The nature of the diarrhea in Crohn's disease depends on the part of the small intestine or colon that is involved. Ileitis typically results in large-volume watery feces. Colitis may result in a smaller volume of feces of higher frequency. Fecal consistency may range from solid to watery. In severe cases, an individual may have more than 20 bowel movements per day and may need to awaken at night to defecate. Visible bleeding in the feces is less common in Crohn's disease than in ulcerative colitis, but may be seen in the setting of Crohn's colitis. Bloody bowel movements are typically intermittent, and may be bright or dark red in colour. In the setting of severe Crohn's colitis, bleeding may be copious. Flatus and bloating may also add to the intestinal discomfort.

Systemic symptoms:
Crohn's disease, like many other chronic, inflammatory diseases, can cause a variety of systemic symptoms. Among children, growth failure is common. Many children are first diagnosed with Crohn's disease based on inability to maintain growth. As Crohn's disease may manifest at the time of the growth spurt in puberty, up to 30% of children with Crohn's disease may have retardation of growth. Fever may also be present, though fevers greater than 38.5 ˚C (101.3 ˚F) are uncommon unless there is a complication such as an abscess. Among older individuals, Crohn's disease may manifest as weight loss. This is usually related to decreased food intake, since individuals with intestinal symptoms from Crohn's disease often feel better when they do not eat and might lose their appetite. People with extensive small intestine disease may also have malabsorption of carbohydrates or lipids, which can further exacerbate weight loss.

Treatment:

Treatment is only needed for people exhibiting symptoms. The therapeutic approach to Crohn's disease is sequential: to treat acute disease and then to maintain remission. Treatment initially involves the use of medications to treat any infection and to reduce inflammation. This usually involves the use of aminosalicylate anti-inflammatory drugs and corticosteroids, and may include antibiotics.
Once remission is induced, the goal of treatment becomes maintaining remission and avoiding flares. Because of side-effects, the prolonged use of corticosteroids must be avoided. Although some people are able to maintain remission with aminosalicylates alone, many require immunosuppressive drugs.

Surgery may be required for complications such as obstructions, fistulas and/or abscesses, or if the disease does not respond to drugs within a reasonable time. For patients with an obstruction due to a stricture, two options for treatment are strictureplasty and resection of that portion of bowel. According to a retrospective review at the Cleveland Clinic, there is no statistical significance between strictureplasty alone versus strictureplasty and resection specifically in cases of duodenal involvement. In these cases, re-operation rates were 31% and 27%, respectively, indicating that strictureplasty is a safe and effective treatment for selected patients with duodenal involvement.


Source : Wikipedia

Celiac Sprue

Introduction:

It is a malabsorption syndrome related to immune reaction to gluten in diet, also called nontropical sprue, celiac disease and gluten sensitive enteropathy (GSE).

Causes:

• Toxic effect of gluten/gliadin (gliadin is a glycoprotein component of gluten)
• immune reaction (antibody to gluten/gliadin)
• adenovirus type 12
• may be autosomal dominant with incomplete penetrance

Physical Findings:

In infants - growth retardation, failure to thrive and irritability. Most patients are thin, emaciated.

Microscopic Findings:

This is a micrograph of a typical celiac disease intestine.

Diagnosis:
There are several tests that can be used to assist in diagnosis. The level of symptoms may determine the order of the tests, but all tests lose their usefulness if the patient is already taking a gluten-free diet. Intestinal damage begins to heal within weeks of gluten being removed from the diet, and antibody levels decline over months. For those who have already started on a gluten-free diet, it may be necessary to perform a re-challenge with 10 g of gluten (four slices of bread) per day over 2–6 weeks before repeating the investigations. Those who experience severe symptoms (e.g. diarrhoea) earlier can be regarded as sufficiently challenged and can be tested earlier.


Prognosis:
Patient do recover and villi regenerate.
Celiac disease associated with increased mortality among patients with malabsorption symptoms.

Early Gastric Carcinoma

This is a gross specimen of an early gastric carcinoma (from Pathology Text).

It shows nodular mucosa, not very apparent from this surface view, but it is very much evident on cut section, showing involvement of mucosa and submucosa, but not the muscularis.

Hirschsprung's disease

Description:

Also called congenital megacolon. Its a disease in which there is congenital absence of parasympathetic innervation of distal intestine.

Pathogenesis:

Physical Findings:

Abdominal distention, occasionally loops of stool-filled bowel palpable, increased rectal sphincter tone, no stool in rectal vault or ampulla, classically explosion of watery stool on removal of finger.

Lab Diagnosis:

• Abdominal x-ray
• Barium enema
• Rectal suction biopsy
• No ganglion cells in submucosal plexus confirms diagnosis

Treatment:

Cured by surgical excision of affected segment.

Acute Gastritis

Description:
Focal damage to gastric mucosa. Also called acute erosive gastritis, gastric erosion, acute hemorrhagic gastritis, stress ulcers.

Causes:

• Aspirin (NSAIDs)
• Ethanol
• Aalkali and acid
• Ischemia
• Steroids, cigarettes, pancreatic enzymes, bile acids
• Severe stress such as sepsis, severe trauma and burns.

Physical Findings:

Often normal, GI bleeding, tachycardia, hypotension, pallor and upper abdominal tenderness.

Diagnosis:

1. Endoscopy shows congestion, friability, superficial ulceration, petechiae, black hemorrhagic areas are superficial erosions
2. Blood in gastric aspirate

Treatment:

1. Antacids, H2 blockers, sucralfate, omeprazoleprochlorperazine for treating uncomplicated nausea and vomiting.
2. For massive bleeding give vasopressin IV or intra-arteriorly to mesenteric artery; contraindicated in coronary artery disease; only temporary treatment.
3. Near-total gastrectomy if uncontrolled bleeding