HPV Parvovirus B19 Adenovirus Cervical Cancer Fifths Disease Warts Slapped cheek Koilocyte
Distinguished future physicians welcome to Stomp on Step 1 the only free tutorials series that helps you study more efficiently by focusing on the highest yield material. I’m Brian McDaniel and I will be your guide on this journey through Papillomavirus, parvovirus adenovirus. If these topics seem a bit random it is just because these are all of the remaining DNA viruses that didn’t warrant their own tutorial. This is the 7th tutorial in my playlist covering all of microbiology. We will start with HPV which I give a high yield rating of 4 on a scale from 0 to 10. It is a very common virus that is transmitted through direct contact. It is nonenveloped (naked) double stranded DNA virus that lives.
In the keratinocytes of the skin and mucus membranes. These infections are most often asymptomatic. However, a small percentage of infections lead to warts (AKA Verrucae) that usually presents with a raised round rough cauliflower lesion. These lesions are formed by a benign epithelial proliferation of the basal keratinocytes. This should make sense since we covered in our cancer tutorial that the term papilloma means a benign outwardly projecting overgrowth with fingerlike projections. Warts usually don’t cause pain, bleeding, or itching. Here the best picture of a wart I could find without copyright restrictions. It is a plantar wart which can be painful.
There are about 10 different subtypes of wart based on their appearance and predilection for certain areas of the body, but that is beyond the scope of the step 1 exam. There are also roughly 200 different serotypes of the virus. We will discuss a few specific high yield serotypes, but for the most part this is also beyond the scope of the exam. A large majority of warts regress spontaneously over the course of weeks or months. The body is usually able to clear the virus without medical intervention. However, clearance of the virus does not necessarily confer immunity to future infections. If the wart causes an unwanted cosmetic appearance it can be removed through a number of different techniques including.
Cryotherapy (freezing) topical salicylic acid (an active metabolite of aspirin). In addition to causing warts in areas like the hand and feet, Human Papillomavirus is also an STD. It is actually the most common Sexually Transmitted Infection worldwide, and is associated with genital warts and various types of genital cancer. Condyloma Acuminatum is a genital wart caused by HPV. HPV serotypes 6 11 are most often associated with genital warts, but rarely associated with genital cancers. However, patients can be infected by multiple subtypes at once so the presence of warts does not rule of cancer. HPV is associated with cancers of the vagina,.
Vulva, penis, and even the oropharynx (I’ll leave it to your imagination to figure out how the virus gets there). However, your focus should be on cervical cancer, because it is by far the most common. There are about a dozen subtypes of Human Papilloma Virus that are considered high risk for genital cancers, but serotypes 16 18 are discussed most on exams. While in most patients the virus is cleared relatively quickly in some patients the virus can remain as an active subal or asymptomatic infection for many years. Over time (often over a decade) these persistent infections are the ones that can lead to cancer. Cancers arise as a result of the viral genome being.
Integrated into the host cell’s DNA. In particular, genes coding for E6 E7 oncogenes are carcinogenic. These viral proteins inactivate tumor suppressors leading to unregulated cell division. In particular E6 inactivates p53 and E7 inactivates rb. Since it takes many years for the viral infection to turn into cancer and early interventions improve outcomes Papillomavirus is an excellent target for screening. A PAP Smear (AKA PAP Test) is a screening test used to look at cells of the cervix in hopes of identifying precancers and cancers before they can become malignant. Using a small brush cells of the transitional zone are removed so they can be examined under a microscope. The transitional.
Zone is where the outer squamous cells â€œtransitionâ€� into the inner glandular columnar cells. This is the most common location of cervical cancer and represents an area of physiologic metaplasia. Koilocytes (AKA Koilocytic Atypia) are irregular squamous epithelial cells seen on PAP smears that can signify HPV infection. These cells have an enlarged darkened nucleus, perinuclear clearinghalo, and an irregular border. Here on the left you can see normal cervical cells and on the right you can see koilocytes. A PAP Smear may be combined with an HPV DNA test which can help identify specific high risk subtypes of the virus and if negative may allow you to decrease the frequency of PAP Smears. There is currently a debate about.