Differential diagnosis, first introduced by Emil Kraepelin, is a systematic approach to distinguishing between diseases or conditions that share similar clinical features. It involves analyzing patient history and physical examination to identify the specific disorder and rule out alternatives, ensuring accurate diagnosis and appropriate treatment. Key steps in this process include collecting patient information, identifying prominent symptoms, and conducting tests to clarify potential diagnoses.

1. Dr. Garima Gupta
Assistant Professor
Department of Psychology
Arya Mahila PG College (Admitted to the privileges of BHU)
Varanasi

2.  Differential Diagnosis was first mentioned by Emil Kraepelin.
 Abbreviation: DDx, ΔΔ, ddx, or DD,
 In DDx, patient's history and physical examination are analysed to
arrive at the correct diagnosis. It includes distinguishing a particular
disease/condition from others disease that have similar clinical
features.
 Differential diagnosis is a systematic method of differentially
diagnosing the pathology from one and other based on shared
sign/symptoms. Thus, it helps identifying the disorder that lacks
unique symptoms or signs.
 It is a systematic diagnostic method that are used to identify the
presence of a an actual disease where multiple alternatives are
plausible.

3.  Therefore, differential diagnosis is a process where we
distinguish disorders that are having similar signs and
symptoms. In this a comparison is done on the basis of
symptoms, where we rule out the possibility of all other
factors/conditions or disorders except the one that can best
account for the existing clinical feature.
 To sum up, differential diagnosis is a condition with more
than one possibility for the diagnosis. The clinician is
required to differentiate between these (more than one
pathology/condition) to determine the actual diagnosis and
plan for appropriate treatment.
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4. 1.A condition where the existing clinical
picture is probably associated with the
different etiological factors i.e. the
symptomatic features are same of
both the pathology but are associated
with different etiology.
2.Another condition where it’s required
is the pathology with considerable
amount of symptomatic overlap.

5. • To narrow down the working
diagnosis.
• To plan/guide medical evaluation
and treatment.
• To rule out life threatening
conditions.
• To assist the doctor to make the
correct diagnosis.

6.  Step-1: Collection of important information of patient. Collected
information is analyzed and synthesized to get clinical features.
 Step-2: Once, the clinical features are identified, an attempt is made
to find which feature is the most prominent part of the presenting
clinical picture.
 Step-3: When the most prominent symptoms are identified, the
clinician questions the patients and tests to rule in or rule out the
possibility of various disorders.
 The clinician tries to identify the possible cause or antecedent
and/or concomitant factors of the existing symptoms/clinical
pictures.
 Further, an attempt is made to rule in or out for the presence of
other associated clinical features.
 The duration of existing or presenting symptoms and the prominent
symptoms are decided