Anatomical pathology

Anatomical pathology is the branch of pathologythat is concerned with the diagnosis of disease based on the gross and microscopic examination of cellsand tissues. The father of the modern Anatomical pathology is the Italian Giovanni Battista Morgagni.

Anatomical Pathology (AP) is one of the two primary certifications offered by the American Board of Pathology. The other is Clinical Pathology(CP).

Role of the anatomical pathologist

Contrary to popular belief, the field mostly concerns the study of tissue obtained from live patients. In fact, almost all tissues removed from a patient for any reason are examined by a pathologist. The autopsy, though, remains an important tool in gaining medical knowledge. Biopsyspecimens are often taken from part of a lesion when the cause of a disease is uncertain or its extent or exact character is in doubt. Vasculitis, for instance, is usually diagnosed on biopsy. Additionally, pathologic examination of a small biopsy can help differentiate between different types of cancerand determine whether a lesion is benign or malignant. In contrast to a biopsy that merely samples a lesion, a larger excisional specimen called a resection may come to a pathologist, typically from a surgeon attempting to eradicate a known lesion from a patient. For example, a pathologist would examine a mastectomy specimen, even if a previous nonexcisional breast biopsy had already established the diagnosis of breast cancer. Examination of the full mastectomy specimen would confirm the exact nature of the cancer (subclassification of tumor and histologic "grading") and reveal the extent of its spread (pathologic "staging").

Procedures

The procedures used in anatomical pathology include:

• Grosspathology, the examination of diseased tissues with the naked eye. This is important especially for large tissue fragments, because the disease can often be visually identified. It is also at this step that the pathologist selects the part that will be processed for histopathology.
• Histopathologyis the Microscopicexamination of stained tissue sections using histologicaltechniques. The standard stains are haematoxylinand eosinbut many others exist. The science of staining tissues sections is called histochemistry. Antibodies can also be used to stain specific proteins, a technique called immunohistochemistry. Specific DNAand RNAmolecules can be identified on sections using the technique of in situ hybridization. When the probe is labeled with fluorescentdye, the technique is called FISH.
• Cytopathologyis the examination of loose cells spread and stained on glass slides using cytologytechniques.
• Electron microscopyis used to identify organelleswithin the cells. Its usefulness has been greatly reduced by immunhistochemistrybut it is still irreplaceable for the diagnosis of kidneydisease, identification of immotile cilia syndromeand many other tasks.
• Tissue cytogeneticscan identify genetics defects, like chromosomaltranslocation.
• Flow immunophenotypingis the determination of the immunophenotypeof cells using flow cytometrytechniques. It is very useful to diagnose the different types of leukemiaand lymphoma.

Subspecialties

Doctors turn to pathologists for help when the diagnosis is not evident. Therefore, pathologists are expected to know many more diseases than clinicians - they are the "doctor's doctor". The amount of knowledge needed is enormous. Since one person cannot possibly know everything, pathologists tend to sub-specialize. Here is a (probably incomplete) list of the commonly recognized sub-specialties:

• Surgical pathology: diagnosis of diseases in organs removed by general surgeons, especially breast, lung, bowel. This is the core of anatomical pathology. Most of these organs are covered by sub-sub specialties:
  • Gastrointestinal pathology: diagnosis of boweldiseases from biopsiestaken by agastroenterologist. One of its sub-sub specialty is hepatopathology, the diagnosis of liverdiseases based on liver biopsy.
  • Uropathology, including diseases of the urinary tractand the male genital tract
  • Cardiac pathology
  • Pulmonary pathology
  • Endocrinepathology
  • Gynecologicalpathology, including diseases of the female genital tractand the placenta
  • soft tissue pathologyand orthopedic pathology
  • E.N.T.Pathology
• Cytopathology
• Neuropathology: diagnosis of diseases from tissues removed by neurosurgeons. Neuropathologists also examine whole brainsand spinal cordsremoved at autopsy.
• Dermatopathology: diagnosis of skindiseases from the histologicalexamination of skin biopsies taken by a dermatologist.
• Ophthalmicpathology
• Hematopathology
• Nephropathology
• Pediatric pathologyand its sub-sub specialty neonatal pathology

Oral & Maxillofacial pathologyis different; the American Boardof Oral and maxillofacial pathology certifies dentistrydoctors, not medical doctors, to practice this sub-specialty of Pathology.

See also

• Pathology
• Clinical pathology
• Forensic pathology
• Molecular pathology
• Veterinarypathology
• Plant pathology

External link

• PathMax, a collection of online Pathology resources
• The Doctor's doctor, a very useful web site for patients and pathologists
• Pathologie Online, online Pathology resources in German
• Pathology Outlines, an online textbook of anatomical pathologyca:Anatomia patològica

es:anatomía patológica fr:anatomo-pathologie

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It uses material from the http://en.wikipedia.org/wiki/Anatomical+pathology Wikipedia article Anatomical pathology.