Hepatitis B (إلتهاب الكبد الوبائى ب)

مقدمة

اللب

ما هو مرض الإلتهاب الكبدى الوبائى (ب)؟

What is hepatitis B?

Hepatitis B is an infectious liver disease. It is caused by the hepatitis B virus (HBV). Infections of hepatitis B occur only if the virus is able to enter the blood stream and reach the liver. Once in the liver, the virus reproduces and releases large numbers of new viruses into the bloodstream.

To combat the disease, the body has several defenses. White blood cells, which protect the body from infections, attack and destroy the infected liver cells. The body also produces antibodies which circulate in the blood to destroy the virus and protect against future infections of hepatitis B. During the infection and recovery process, the liver may not function normally causing illness that affects the entire body.

For reasons that are not completely understood, 10 percent of people who develop hepatitis B become carriers of the disease. Their blood remains infected for months, years, sometimes for life. Seventy percent of carriers develop chronic persistent hepatitis B. Most do not appear to be ill. The remaining 30 percent of carriers experience continuous liver disease. This condition often progresses to cirrhosis and then, after 30 to 40 years, possibly to liver cancer. At present, there is no way of curing carriers. The risk of becoming a chronic carrier is related inversely with a person’s age when infected. For example, the risk of an infant becoming a carrier is 90-95% whereas the risk of an adult becoming a carrier is 3-10%.


باء التهاب الكبد هو مرض الكبد المعدية. و هو ناجم عن فيروس التهاب الكبد البائي (الفيروس). عدوى التهاب الكبد باء يحدث إلا إذا كان الفيروس قادر على الدخول في مجرى الدم وتصل الى الكبد. مرة واحدة في الكبد ، ويستنسخ الفيروس والنشرات أعداد كبيرة من الفيروسات الجديدة في مجرى الدم.

لمكافحة المرض ، ودفاعات الجسم عدة. خلايا الدم البيضاء ، التي تحمي الجسم من العدوى ، ومهاجمة وتدمير خلايا الكبد المصابة. الجسم ينتج الأجسام المضادة التي تعميمها أيضا في الدم لتدمير الفيروسات وحماية ضد الالتهابات في المستقبل باء التهاب الكبد وعدوى خلال عملية الانتعاش ، والكبد قد لا تعمل بشكل طبيعي تسبب مرض يؤثر على الجسم كله.

وذلك لأسباب غير مفهومة تماما ، و 10 في المئة من الاشخاص الذين يصابون بالتهاب الكبد البائي تصبح ناقلة للمرض. دمهم لا تزال مصابة لشهور وسنوات ، وأحيانا مدى الحياة. سبعون في المئة من ناقلات تطوير التهاب الكبد المزمن المستمر باء معظم لا يبدو أن سوء. ما تبقى من 30 في المئة من ناقلات تجربة مستمرة أمراض الكبد. هذا الشرط تقدم في كثير من الأحيان إلى تليف الكبد وبعد ذلك ، بعد 3-40 سنوات ، وربما إلى الإصابة بسرطان الكبد. في الوقت الحاضر ، لا توجد وسيلة لعلاج الناقلين. ويرتبط خطر أن يصبح الناقل المزمنة عكسيا مع عمر الشخص عند المصابين. على سبيل المثال ، فإن خطر رضيع تصبح الناقل 90-95 ٪ في حين أن خطر بالغ تصبح الناقل 3-10 ٪.


Key facts
Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
The virus is transmitted through contact with the blood or other body fluids of an infected person - not through casual contact.
About 2 billion people worldwide have been infected with the virus and about 350 million live with chronic infection. An estimated 600 000 persons die each year due to the acute or chronic consequences of hepatitis B.
About 25% of adults who become chronically infected during childhood later die from liver cancer or cirrhosis (scarring of the liver) caused by the chronic infection.
The hepatitis B virus is 50 to 100 times more infectious than HIV.
Hepatitis B virus is an important occupational hazard for health workers.
Hepatitis B is preventable with a safe and effective vaccine.


Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus. It is a major global health problem and the most serious type of viral hepatitis. It can cause chronic liver disease and puts people at high risk of death from cirrhosis of the liver and liver cancer.

Worldwide, an estimated two billion people have been infected with the hepatitis B virus (HBV), and more than 350 million have chronic (long-term) liver infections.

A vaccine against hepatitis B has been available since 1982. Hepatitis B vaccine is 95% effective in preventing HBV infection and its chronic consequences, and is the first vaccine against a major human cancer.


حقائق أساسية
التهاب الكبد باء هو عدوى فيروسية تصيب الكبد ويمكن ان تسبب على حد سواء الحادة والمزمنة المرض.
وينتقل الفيروس من خلال الاتصال مع الدم أو سوائل الجسم الأخرى من شخص مصاب -- وليس عن طريق المخالطة العارضة.
حوالي 2 مليار شخص حول العالم قد اصيبوا بالعدوى الناجمة عن الفيروس ، وحوالي 350 مليون يعيشون مع مرض كبدي مزمن. ما يقدر ب 600 000 شخص يموتون كل عام بسبب الآثار الحادة والمزمنة من التهاب الكبد ب.
حوالي 25 ٪ من البالغين ، الذين أصيبوا بالعدوى بشكل مزمن أثناء مرحلة الطفولة ، نحبهم لاحقا بسبب سرطان الكبد أو تليف الكبد (تندب الكبد) بسبب الإصابة المزمنة.
فيروس التهاب الكبد البائي هو 5-10 مرات أكثر من فيروس نقص المناعة البشرية المعدية.
فيروس التهاب الكبد البائي هو الخطر المهم المهنية للعاملين الصحيين.
التهاب الكبد باء يمكن الوقاية منه مع لقاح آمن وفعال.


التهاب الكبد باء عدوى فيروسية تصيب الكبد وبإمكانها تهديد حياة الناجمة عن فيروس التهاب الكبد البائي. هو مشكلة صحية عمومية كبرى وأخطر أنواع التهاب الكبد الفيروسي. ويمكن أن يسبب مرض كبدي مزمن وتعريض الناس لمخاطر الوفاة جراء تليف الكبد وسرطان الكبد.

في جميع أنحاء العالم ، وقد تم إصابة ما يقدر بنحو ملياري شخص بفيروس التهاب الكبد البائي ، وأكثر من 350 مليون نسمة يعانون من التهابات مزمنة في الكبد (طويل الأجل).

وثمة لقاح ضد التهاب الكبد باء متاحة منذ عام 1982. ويضمن هذا اللقاح نجاعة بنسبة 95 ٪ في الوقاية من العدوى وآثارها المزمنة ، وهو أول لقاح ضد سرطان بشرية كبيرة.


المصادر:

http://www.ccohs.ca/oshanswers/diseases/hepatitis_b.html

http://www.who.int/mediacentre/factsheets/fs204/en/


تعريف آخر:

Hepatitis B is a serious liver infection caused by the hepatitis B virus (HBV). For some people, hepatitis B infection becomes chronic, leading to liver failure, liver cancer, or cirrhosis — a condition that causes permanent scarring of the liver.

Most people infected with hepatitis B as adults recover fully, even if their signs and symptoms are severe. Infants and children are much more likely to develop a chronic hepatitis B infection. Although no cure exists for hepatitis B, a vaccine can prevent the disease. If you're already infected, taking certain precautions can help prevent spreading HBV to others.


التهاب الكبد باء التهاب الكبد الخطيرة الناجمة عن فيروس التهاب الكبد البائي. بالنسبة لبعض الناس ، والتهاب الكبد باء العدوى يصبح المزمن ، مما يؤدي إلى فشل الكبد وسرطان الكبد وتليف الكبد أو -- وهو الشرط الذي يسبب ندبات دائمة في الكبد.

معظم الأشخاص المصابين بفيروس التهاب الكبد البائي الكبار يشفون تماما ، حتى لو علامات وأعراض وخيمة. الرضع والأطفال هم أكثر عرضة للاصابة بالعدوى المزمنة باء التهاب الكبد. وبالرغم من عدم وجود علاج لالتهاب الكبد باء ، لقاح يمكن أن يمنع هذا المرض. إذا كنت مصابة مسبقا ، يمكن اتخاذ احتياطات معينة تساعد على منع انتشار الفيروس إلى الآخرين.

المصدر:

http://www.mayoclinic.com/health/hepatitis-b/ds00398

صور توضيحية(شرائح)للكبد السليم والكبد المصاب بمرض الإلتهاب الكبدى الوبائى(ب):



الكبد الطبيعى



الكبد المصاب بمرض الإلتهاب الكبدى الوبائى(ب)



Normal Liver
Blood flows into the liver via the hepatic veins (in the portal triad) and out of the liver via the central veins in the lobules.


طبيعي الكبد
يتدفق الدم الى الكبد عبر الأوردة الكبدية (في الثالوث البوابة) والخروج من الكبد عبر الأوردة المركزية في الفصيصات.



Hepatitis B
The Hepatitis B virus is extremely contagious and causes widespread necrosis of the liver. The destruction encompasses both the lobules and the interstitium making this tissue almost unrecognizable.



التهاب الكبد باء
فيروس التهاب الكبد باء معد للغاية ويسبب نخر على نطاق واسع في الكبد. تدمير يشمل كلا من الفصيصات وجعل هذا النسيج الخلالي التعرف تقريبا.


المصدر:

http://www.hepatitis-central.com/hcv/liver/histopath.html

أسبابه وكيفية إنتقاله:

Hepatitis B infection is caused by the hepatitis B virus (HBV). HBV is passed from person to person through blood, semen or other body fluids. When HBV enters your liver, it invades the liver cells and begins to multiply. This causes inflammation in the liver and leads to the signs and symptoms of hepatitis B infection


The virus can survive outside the body for at least 7 days and still able to cause infection


Blood

Direct contact with infected blood can transmit the hepatitis B virus through:

punctures of the skin with blood-contaminated needles, lancets, scalpels, or other sharps
splashes to skin bearing minute scratches, abrasions, burns, or even minor rashes
splashes to mucous membranes in the mouth, nose, or eyes
To a lesser extent, indirect contact with blood-contaminated surfaces can also transmit the hepatitis B virus. The virus may be stable in dried blood for up to 7 days at 25?C. Hand contact with blood-contaminated surfaces such as laboratory benches, test tubes, or laboratory instruments may transfer the virus to skin or mucous membranes.

Saliva

Saliva of people with hepatitis B can contain the hepatitis B virus, but in very low concentrations compared with blood. Injections of infected saliva can transmit the virus, so bite injuries can also spread the disease. There are no reports of people getting hepatitis B from mouth contact with infected CPR manikins or mouthpieces of musical instruments.

Other Body Fluids and Tissues

Hepatitis B is found in semen, vaginal secretions, and breast milk. The virus can be transmitted during unprotected sexual intercourse, and from mother to infant during birth and through breast feeding.

Synovial fluid (joint lubricant), amniotic fluid, cerebrospinal fluid, and peritoneal fluid (found in the abdominal cavity) can contain the hepatitis B virus, but the risk of transmission to workers is not known.

Feces, nasal secretions, sputum, sweat, tears, urine, and vomit have not been implicated in the spread of hepatitis B. Unless they are visibly contaminated with blood, the risk of contracting hepatitis B from these fluids in the workplace is practically nonexistent.

Hepatitis B is not transmitted by casual contact. For example, hospital employees who have no contact with blood, blood products, or blood-contaminated fluids are at no greater risk than the general public. However, the virus can spread through intimate contact with carriers in a household setting. Why this happens is not completely understood. Somehow, the virus can find its way into the bloodstream of fellow family members possibly because of frequent physical contact with the small cuts or skin rashes. The virus can also spread through biting and possibly by the sharing of toothbrushes or razors. It is not spread through sneezing, coughing, hand holding, hugging, breastfeeding, sharing eating utensils, water or food.


What occupations have increased risk of hepatitis B?

The risk of acquiring hepatitis B from the workplace depends on the amount of exposure to:

human blood or blood products, or other body fluids and tissues known to transmit the hepatitis B virus
needlestick injuries or other puncture injuries from sharp instruments contaminated with blood
close contact with people who carry the hepatitis B virus in family or institutional residence settings
Blood tests show that certain occupational groups have different risks of getting hepatitis B.

table1

Risks to Occupational Groups
Percentage of people having evidence of past hepatitis B infection Occupational Group
High (over 20%) Pathologists, biochemistry and hematology laboratory personnel, dialysis staff
Intermediate (7-20%) Hospital nurses, laboratory personnel other than those in high risk groups, staff of institutions for the developmentally handicapped, dentists
Low (less than 7%) Administrative hospital staff, medical and dental students, healthy adults


In general, occupational groups with increased risk include:

health-care workers repeatedly exposed to blood or blood products or those who are at risk of needlestick injury
dentists, dental assistants, and dental hygienists
certain staff members of institutions for the developmentally handicapped
staff of institutions where workers may be exposed to aggressive, biting residents
embalmers



المصدر:

http://www.mayoclinic.com/health/hepatitis-b/DS00398/DSECTION=causes

http://www.ccohs.ca/oshanswers/diseases/hepatitis_b.html

الأعراض:


Symptoms:

Signs and symptoms of hepatitis B usually appear about two to three months after you've been infected and can range from mild to severe. Signs and symptoms of hepatitis B may include:

Abdominal pain
Dark urine
Joint pain
Loss of appetite
Nausea and vomiting
Weakness and fatigue
Yellowing of your skin and the whites of your eyes (jaundice)


Most infants and children with hepatitis B never develop signs and symptoms.

The same is true for some adults.


References

Sept. 5, 2009

© 1998-2010 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "EmbodyHealth," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.


المصدر:

http://www.mayoclinic.com/health/hepatitis-b/DS00398/DSECTION=symptoms

What are the phases of hepatitis B infection?

Immune-tolerant phase -

This phase of chronic hepatitis B infection is mainly seen in children infected at birth. The virus reproduces aggressively but causes little inflammation. The body has not yet been triggered to fight the virus actively. This phase may last into adulthood.


Immune-active phase -

For unknown reasons, the body realizes it is infected with a foreign virus and mounts a raging defense. Unfortunately, this aggressive response to the virus leads to inflammation that can damage the liver. Most children will enter the inactive state but some will retain active inflammation. The children "stuck" in this phase of hepatitis B infection are the most likely to develop liver damage or liver cancer.


Inactive hepatitis B phase -

Most children with active inflammation have gradual reduction in liver inflammation and enter the inactive phase. This phase is a chronic carrier state in which ongoing liver damage is minimal but these children can still spread the virus to others through contact with blood.


المصدر:

http://www.drtummy.com/index.php?option=com_content&view=article&id=152:hepatitis-b&catid=54:headers&Itemid=57