Tazria- Mezorah: Diagnosis

Much of these parshioth  deals with the identification of disease.  The passage of time, and with it, the alterations in  the prevalence of various diseases, makes it impossible to associate  tzoraas with a modern disorder.  But principles of health care  are seen in the process that is described. 

The person afflicted with tzoraas shows the lesion to the Cohein, A person does not diagnose herself.  only the designated, presumably trained observer can make the diagnosis.  An objective outsider is needed.  The affected person may exaggerate the abnormality because of anxiety; or minimize it so that he can avoid the difficult situation. 

The trained Priest using  a set of criteria to determine whether or not the lesion fits  the diagnosis. The visual criteria: color, quality of the hair, etc., are also embedded in a special diagnostic language. The lesions have names: seais, bahereth, etc that convey properties that are lost on the uninitiated.  The secret language of doctors, in our times, adds to their mystique.  It takes some  background to understand  the significance  of the abl oncogene or JAK2.  But these names convey meaning in terms of the prognosis and teatment of disease to the cognoscenti. 

Since Virchow, in the mid 1800's, the microscopic appearance has become the accepted methodogy for diagnosis. To classify disease, a biopsy is needed to obtain a microscopic  view. This current tradition ( which may soon  be supplanted by molecular analysis) makes us look askance at diagnoses made by visual inspection ( although dermatologists make such diagnoses quite accurately).  As our understanding of the molecular mechanisms of disease improves, we may feel the same inadequacy about a microscopic diagnosis that has not had gene sequencing and immunologic characterization. 

The parsha recognizes that doubt about the nature of a lesion will arise.  Provisions for  re-examination are outlined.  It is the spread and/or the persistence of the lesion that identifies its severity. Perhaps these principles should be applied more broadly in modern medicine.  Our predictions about the behaviors of certain diseases leads to their treatment.  But sometimes, a diagnosis that sounds terrible- leukemia, lymphoma- can be associated with a long, symptom free course.  Sometimes the interventions are more destructive than beneficial,   There is  sometimes a place for watching the course  before deciding on treatment,  

There is no substitute for careful observation.