Pathology is a markedly varied specialty of medicine which focuses on the nature and causes of diseases. It spans all aspects of medicine from diagnostic testing to monitoring blood parameters of chronic diseases, to blood transfusion technologies and genetic research, including emerging molecular testing for malignancies. Pathology is vital to all aspects of diagnostic and research medicine. It is broadly divided into anatomic and clinical pathology. Anatomic pathologists, such as those at Pennsylvania Specialty Pathology, perform the microscopic diagnosis of diseases through tissue samples and cells in exfoliated samples of fluids, (cytopathology). Anatomic pathologists can also perform autopsies. Clinical pathology (not performed at Pennsylvania Specialty Pathology) refers to the diagnosis or monitoring of diseases through blood and body fluid samples, microbiologic cultures and transfusion pathology.
Doctors specializing in anatomic and clinical pathology train for a period of 4-5 years after 4 years of medical school. After that period, he or she may go on to subspeciailize in another area (example dermatopathology and gastrointestinal pathology). At the completion of training in anatomic and clinical pathology, board certification in anatomic and/or clinical pathology is needed in order to practice in the field in the United States.
Dermatopathology is a subspecialty of dermatology and surgical pathology which involves the study of skin diseases at the microscopic level. For maximum benefit of the patients, dermatopathologists work in close association with dermatologists, family practitioners and general and plastic surgeons. Certification in dermatopathology in the United States requires completion of 4 years of medical school, followed by residency training of either 3 years in dermatology or 3-4 years in anatomic pathology, followed by 1-2 years of dermatopathology training. Dermatopathology training requires rotating and training in both dermatology and pathology. Following subspecialty training in the field, certification in dermatopathology is granted after successfully completing an examination conducted jointly by the American Board of Pathology and the American Board of Dermatology.
Read more about skin cancer.
The skin is the largest organ in the body and there are more than 1,500 different tumors and rashes affecting the skin. In addition, there are subtle changes in lesions seen at the microscopic level, especially in moles, which makes the distinction of benign from malignant difficult. Hence, a doctor who has subspecialized in the field and has experience in evaluating skin biopsies would be best at handling these diagnostic challenges.
Cytopathology is the diagnosis of disease by examination of individual cells. For example, cells removed in a Pap smear can be smeared on a slide and evaluated for disease. Similarly, cells in a urine sample or other body fluids can be evaluated for diseases.
Gastrointestinal pathology is a subspecialty of pathology which focuses on the study of diseases in the gastrointestinal tract, including the esophagus, stomach, large and small intestines. The gastrointestinal pathologist is also trained to diagnose diseases in the liver, gallbladder and pancreas. The specialists in this field hence, examine biopsies and resections for benign, premalignant and malignant diseases. Subspecialization in gastrointestinal pathology requires 4 years of medical school, followed by 3-4 years of training in anatomic pathology, followed by a 1-2 year period of training in gastrointestinal pathology.
Read more about colon cancer.
Since a gastrointestinal pathologist has dedicated time studying the diseases of the gastrointestinal tract, he or she would be most capable of diagnosing diseases related to this organ system. At endoscopy, only small biopsy samples are provided, hence subtle changes and the application of criteria for making the distinction ranging from the spectrum of benign to premalignant to malignant are best achieved by an individual trained in the field.
Carcinoma of the cervix is the second leading cause of cancer related deaths in women worldwide with a total of over 300,000 deaths per year. In 2009, the estimated number of new cases in the United States was 11,270 with 4,070 deaths (www.cancer.gov). Human papillomavirus (HPV) is the most common sexually transmitted infectious agent worldwide and has been found in 27% of women between the ages of 14 and 59 in the United States. There are over 100 different types, some known to cause papillomas or warts at various body sites while others are thought to be oncogenic or cause cancer at various sites. The human papillomavirus has been implicated in up to 99% of cervical cancers. HPV can be further categorized into high risk (22 known types), low risk (20 known types) and unknown risk. High risk HPV types are more significantly associated with dysplasia (both low and high grade) as well as cervical cancer. HPV type 16 has consistently been the most common high risk HPV type identified worldwide and in combination with HPV type 18 accounts for approximately 70% of all cervical cancers. Low risk types are associated with genital warts, and HPV types 6 and 11 are the most common, accounting for 90% of the cases.
There are a number of tests used for the detection of human papillomavirus from Pap smears. The first, the Hybrid Capture II (HCII) test can detect 13 different high risk types, while another test (Cervista) detects 14 high risk types. These tests are reported as positive or negative for high risk HPV depending on the detection of one of these 13 or 14 types, respectively. Additionally, Cervista can also specifically identify types 16 and 18. At Pennsylvania Specialty Pathology, the testing method utilized was developed by Access Genetics and is based on polymerase chain reaction. By this method we are able to specifically identify and subtype any HPV present and then assign a risk category. Hence, for each HPV type identified as positive, a specific subtype will be named in the report. This facilitates follow up of the HPV subtype for persistence of infection by a specific type of human papillomavirus. This persistence of infection by certain subtypes is a risk factor for development of dysplasia and cancer.
In November 2009, the American College of Obstetricians and Gynecologists (ACOG) revised the guidelines for Pap smear screening, utilizing HPV testing in certain age groups (women older than 30 years). It is used as a screening test in combination with the Pap smear. Women, especially those at risk, should consult with their doctor to determine their best option for the screening and prevention of cervical cancer.
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Chlamydia and gonorrhea are sexually transmitted diseases and in the United States, adolescent girls and women between the ages of 15 and 24 accounted for approximately half of the chlamydia cases and 1/3 of the gonorrhea cases in 2008. This makes these two diseases the first and second most common infectious diseases in this age group nationally. Chlamydia is caused by the bacteria Chlamydia trachomatis which, if left untreated, can damage a woman’s reproductive organs and affect her ability to have children. Women are often asymptomatic. Chlamydia can also be passed from an infected mother to her baby during vaginal childbirth.
The CDC recommends yearly chlamydia testing of all sexually active women age 25 years or younger and older women with risk factors for chlamydia infection (women with a new or multiple sexual partners), and all pregnant women.
Gonorrhea is the second most common sexually transmitted disease in the United States and it is caused by the bacteria Neisseria gonorrhea. Gonorrhea can infect the cervix, uterus, fallopian tubes, the urethra, mouth, throat, eyes and anus. Gonorrhea can be asymptomatic, especially in men. Symptoms and signs when present include a burning sensation when passing urine, white, yellow or green discharge from the penis or vagina and abnormal bleeding between periods. Infection of the anus can result in discharge, itching, soreness and bleeding. In women, the symptoms are often mild and women may even be asymptomatic.
Gonorrhea can be passed on during childbirth to the baby and can result in blindness, joint infection, or severe sepsis in the baby. Women with untreated gonorrhea may proceed to develop pelvic inflammatory disease which can result in an increased risk of infertility and ectopic pregnancies.
At Pennsylvania Specialty Pathology, molecular testing for chlamydia and gonorrhea can be performed on the same Pap smear vial, without the need for an additional sample.
Read more about Chlamydia.
Read more about Gonorrhea.