A 15 year old girl complains of back pain. A neurological examination and various blood and radiological examinations are negative—except for the MRI scan (“I'm sure there'll be nothing, but let's be certain”). The scan shows a mild focal dilatation of the central canal of the spinal cord over two vertebral levels in the mid-dorsal region. She is referred for a neurosurgical opinion with a presumed diagnosis of syringomyelia. Her parents surf the net. Now they know all about small muscle wasting, intractable pains, dissociated sensory loss, and the strong likelihood of progressive neurological deterioration. They also learn that a major spinal (or, worse still, craniospinal) operation is the only way to alter this gloomy prognosis. They arrive for the consultation shattered but resigned.

Since I just recovered from the flu... Let's talk about viruses:

• Hemagglutinin
• Neuraminidase
• Fusion protein

These are called "surface proteins" that are present on some viruses.

The function of hemagglutinin is to bind to the cell surface to initiate infection of the cell. In the clinical laboratory, the hemagglutinin agglutinates red blood cells, which is the basis of a diagnostic test called the hemagglutination inhibition test.
The hemagglutinin is also the target of neutralizing antibody (i.e., antibody against the hemagglutinin inhibits infection of the cell).

The neuraminidase cleaves neuraminic acid (sialic acid) to release progeny virus from the infected cell. The hemagglutinin functions at the beginning of infection, whereas the neuraminidase functions at the end. Neuraminidase also degrades the protective layer of mucus in the respiratory tract. This enhances the ability of the virus to gain access to the respiratory epithelial cells.

Both of them are present on the surface of the influenza virus (and many others).

They all belong to the class of neuraminidase inhibitors (except for a relatively new drug). They inhibit the release of virus from infected cells. This limits the extent of the infection by reducing the spread of virus from one cell to another. They are effective against both influenza A & B. They are most effective when taken within 48 hours of onset of symptoms.

Oseltamivir (Tamiflu) & Zanamivir are the most common drugs in this class. There is a fear that the virus might develop resistance to these drugs, which is why we only use them in severe illness and/or in people with risk factors.

Baloxavir marboxil is a new antiviral drug against influenza. It's a cap-dependent endonuclease inhibitor (CENI). Simply stated: it inhibits viral replication. And it's effective even against oseltamivir-resistant strains of the virus.

Now...

In infants, RSV is an important cause of lower respiratory tract diseases such as bronchiolitis and pneumonia. RSV is also an important cause of otitis media in young children.
In older children and young, healthy adults, RSV causes respiratory tract infections such as the common cold and bronchitis. However, in the elderly (people older than 65 years of age) and in adults with chronic cardiopulmonary diseases, RSV can cause severe lower respiratory tract disease, including pneumonia.

The reason why the severity of RSV infection is reduced with age (except for the elderly) is that IgA respiratory antibody reduces the frequency of RSV infection as a person ages.

virtually everyone has been infected by RSV by the age of 3 years.
RSV also causes outbreaks of respiratory infections in hospitalized infants; these outbreaks can be controlled by handwashing and use of gloves, which interrupt transmission by hospital personnel.

Why is it called a "syncytial" virus?
Because it makes cells fuse and clump together and become one huge multi-nucleated cell (called syncytium).

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The fusion protein is present on RSV surface. It causes cells to fuse, forming multinucleated giant cells (syncytia), which give rise to the name of the virus.

اكاديمية نيرسنك لنك دليل المبتدئين في رحلة التمريض الاكاديمية.

نوفر لكم نصائح و محاضرات لامتحانات التمريض بفعالية واستراتيجيات الاختبار.

نوفر لك بيئة تعليمية داعمة ومرنة تلائم جدولك المزدحم.

تتابعنا لمزيد من التفاصيل حول الخدمات والعروض! 📚💡

#التمريض

Streptococcus bacteria

Anti-epileptic drugs for treatment of absence seizures:
• Ethosuximide (1st-line).
• Lamotrigine.

We avoid giving valproic acid (depakine) for women of childbearing age because of risk of teratogenicity.