​Differential diagnosis of pelvic inflammatory disease
-actinomycosis 
-prolonged intrauterine device 
-tuberculosis salpingitis
-cystitis 
-diverticulitis 
-degeneration of leiomyoma 
-fibroid 
-tubo-ovarian abscess
-ovarian torsion 
-ruptured ovarian cyst or tumor 
-septic abortion 
-appendicitis 
-ectopic pregnancy 

​Differential diagnosis of pediculosis ( pubic lice)
-anogenital pruritus 
-scabies 
-eczema 
-atopic dermatitis 

Differential diagnosis of pediculosis ( body lice) 
-urticaria 
-dermatitis herpetiformis 
-scabies 
-impetigo 

Differential diagnosis of pediculosis ( head lice) 
-impetigo 
-hair casts 
-hair debris 
-seborrheic dermatitis 

​Differential diagnosis of Pauci Immune Glomerulonephritis (ANCA+) 
-Microscopic polyarteritis 
-Churg – Strauss Syndrome 
-wegener- granulomatosis 

​Differential diagnosis of Patent Ductus Arteriosus 
-ventricular septal defect
-aortic stenosis 
-mitral regurgitation 

​Differential diagnosis of Parvovirus Infection ( erythema infectiosum) 
-hepatitis 
-arthritis due to rheumatoid arthritis, systemic lupus erythematosus 
-drug eruption 
-Scarlet fever 
-measles 
-rubella ( German measles)
-exanthem subitum ( roseola) 
primary HIV infection 
-infectious mononucleosis 

​Differential diagnosis of causes of paroxysmal supraventricular tachycardia 
-Wolff Parkinson White Syndrome 
-atrial ventricular re –entry tachycardia 
-atrioventricular node re –entry tachycardia 
-digitalis toxicity 

​Differential diagnosis of paronychia 
-hypoparathyroidism 
-bacterial infection
-finger pad infection 
-felon 
-celiac sprue 
-acrodermatitis enteropathica 
-reactive arthritis ( Reiter’s syndrome) 

​Differential diagnosis of Parkinsonism 
-West Nile Virus infection 
-drugs such as antipsychotics, reserpine, metoclopramide 
-creutzfeldt- Jakob disease
-cortical – basal ganglionic degeneration 
-progressive supranuclear palsy 
-Shy –Drager syndrome 
-normal pressure hydrocephalus 
-Huntington’s disease
-Wilson’s disease 
-depression 
-essential tremor 
-vascular parkinsonism 
-Parkinson’s disease