After collecting the diseased tissues, they are first stabilized by placing in a fixative, to prevent decay. Formalin (10% formaldehyde in water) is the fixative used normally.
- The stabilized sample tissues are first transferred to a container where permitted reagents are allowed to act on the tissues.
- Concentrated ethanol helps to dehydrate the tissues. Toluene or Xylene is used after the above procedure to immerse the tissues followed by hot liquid paraffin wax. This process takes 12 to 16 hours, during which paraffin replaces the water in the tissue turning it soft and moist. Now the sample is ready for embedding.
- The tissue is transferred and set in a mold. During this process of embedding, additional paraffin is added to prepare a hard paraffin block.
- Microtome is used to section the embedded tissues into very thin sections of about 3-7 micrometer in thickness. These thin layers or sections are now ready for microscopic study.
- One or more pigments are used to stain the sections to view the details clearly. A combination of hematoxylin and eosin is used to stain the tissues. The cytoplasm pink is got by using eosin and nuclei blue by hematoxylin. Saffron, silver salts and some artificial dyes are the other compounds used to color tissue sections. For staining specific proteins, carbohydrates and liquids, antibodies are also used. The technique known as immunohistochemistry has helped scientists in the microscopic studies to identify different categories of cells specifically.
- A medically qualified expert or pathologist examines the histological slides microscopically.
Systemic Lupus Erythematosus
Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease that surfaces as inflammation and damage to various parts of the body and its tissues. Lupus can affect the joints, skin, heart, lungs, blood vessels, brain and kidneys. Systemic Lupus Erythematosus affects the blood vessels and connective tissues of the skin. Since the body turns against itself, the tissues become inflamed and swollen. Most often, SLE manifests itself with a butterfly-rash and pain in the joints. This disease is more pronounced among persons of Afro-Caribbean and Asian origin. Women are more likely to be afflicted by Systemic Lupus Erythematosus.
A patient suffering from Systemic Lupus Erythematosus experiences painful swelling in the joints, skin rashes, extreme fatigue, fever and infections due to weakened immune system. Scaly sores on the face (discoid rash) and butterfly-shaped rash on the bridge of the nose (malar rash) are also noticed. SLE also leads to serositis - inflammation in the linings of the hear, lungs and abdomen. There may be weight loss, vomiting and diarrhea. SLE can also cause swollen glands and sensitivity to cold. While symptoms of SLE are often noticed in the years of 15 - 45, it can even occur earlier or later.
This disease tends to appear in periodic flare-ups. Often diagnosis of systemic lupus erythematosus takes time. Blood tests are conducted for checking for the presence of antinuclear antibodies (ANA). Chest x-rays and urine analysis are done. Inflammation levels are checked with sedimentation rate (ESR) or C-reactive protein (CRP). While there is no cure for systemic lupus erythematosus, corticosteroids and anti-inflammatory drugs are prescribed to relieve pain and swelling. Immunosuppresants are also used in the treatment of SLE. Physiotherapy is used to give relief to the patient from pain in the joints.
Sarcoidosis
Sarcoidosis is a rare autoimmune disease where the body's own tissues are attacked leading to small lumps (granulomas). It can affect the lungs, heart, brain, skin and nervous system, eyes and other organs. Sarcoidosis usually affects the lungs or lymph nodes. The skin, liver and eyes are also often affected. Granulomas are small scars on the affected organs. These granulomas are very small and are visible only under a microscope. Tiny granulomas clump together and cause a big scar. Scarring affects the normal functioning of the affected organ. This disease has a tendency to affect more than one organ at a time. In its active phase, sarcoidosis manifests as scar tissues on the affected organs. When sarcoidosis is in a non-active phase, the granulmomas do not grow. Sarcoidosis cases are more pronounced among African -Americans. The highest occurences of Sarcoidosis are noticed among Scandinavians and red-haired Irish women. Sarcoidosis was originally called Hutchinson's disease or Boeck's disease.
Sarcoidosis is treated according to its extent and severity. Symptoms of sarcoidosis include arthritis in the ankles and disturbed heart rhythms. In most cases of mild sarcoidosis, the inflammation is resolved on its own. In severe cases, the damage is permanent. When vital organs are affected by sarcoidosis, it results in death. In many cases, sarciodosis does not manifest in any symptoms. A patient suffering from sarcoidosis notices skin and lung problems, weight loss and fatigue. There may be eye problems and arthritis. Patients suffering from this condition may notice shortness of breath and prolonged cough. Skin lesions may appear. Sarcoidosis is noticed during chest x-rays, blood tests and pulmonary function tests. Biopsies of skin lesions or lymph nodes can help in diagnosing sarcoidosis. Oral steroiods such as prednisone or prednisolone are used in the treatment of sarcoidosis. Topical creams or ointments are used to treat sarcoidosis of the skin or eyes.
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