Differential Diagnosis

Question 1

DDx fever of unknown origin

Answer 1

Infections
Autoimmune
Neoplasm
Drug-induced (drug fever)

Question 2

DDx back pain

Answer 2

Musculoskeletal 
Scoliosis 
Spondylolysis
Discogenic (disc herniation)
Neoplasm
Rheum (ankylosing spondylitis)
TB of spine

Question 3

DDx abnormal uterine bleeding

Answer 3

Anovulatory cycles
Pregnancy
Infection
Endocrine disorder (PCOS, hypothyroid)
Hormonal contraceptives
Bleeding disorder (Von willebrands)

Question 4

DDx syncope

Answer 4

Vasovagal
Orthostatic
Arrhythmia
Hypertrophic cardiomyopathy 
Prolonged QT
WPW
Ingestion
Seizures
Hypoglycemia
Electrolyte abnormalities

Question 5

DDx stridor

Answer 5

Croup (laryngotracheobronchitis)
Bacterial tracheitis
Foreign body
Subglottic stenosis
Epiglottis 
Tracheomalacia
Tracheal hemangioma
Vascular rings
Diphtheria
Allergic reaction

Question 6

DDx seizures

Answer 6

Infections
Febrile seizures
Metabolic
Ingestion
Neoplasm
Mass lesion
Vasculitis
Autoimmune

Question 7

List 4 common causes of dehydration

Answer 7

1. GI losses (diarrhea, remiss)
2. Inadequate fluid intake
3. Excessive renal losses
4. Increased insensible losses (fever, sweating, burns)

Question 8

Ddx of apnea

Answer 8

1. CNS: seizure, breath holding
2. Infection: meningitis, bronchiolitis, sepsis, croup, infant botulism, pertussis
3. Cardiac: arrhythmia
4. GI: reflux
5. Metabolic: hypoglycemia, inborn error of metabolism, toxin
6. Trauma: head injury accidental or nonaccidental
7. Prematurity

Question 9

Ddx life threatening abdominal pain.

Answer 9

1. Appendicitis
2. Intussusception
3. Incarcerated hernia
4. Trauma
5. Tumors
6. Sepsis
7. Volvulus
8. Ectopic pregnancy
9. DKA
10. Intra-abdominal abscess
11. Aortic aneurysm
12. Toxic ingestion (iron, lead, aspirin)

Question 10

Ddx altered mental status

Answer 10

1. Dehydration
2. Ingestion
3. Trauma
4. Hypoxia or hyperthermia
5. intussusception
6. Brain mass
7. Occult trauma
8. Postictal
9. VP shunt problem
10. Meningitis or encephalitis
11. Metabolic (hypoglycemia, etc)
12. Reyes syndrome, rarities
13. CVA
14. HUS (2/2 uremia)
15. Functional

Question 11

Ddx of abdominal pain in children older than 3 years

Answer 11

1. Appendicitis
2. Mesenteric lymphadenitis
3. gastroenteritis
4. Meckel diverticulitis
5. Intestinal obstruction
6. Constipation
7. Inflammatory bowel disease
8. Biliary colic, cholecystitis
9. UTI
10. Kidney stone
11. Systemic illness (PNA, HSP, HUS, sickle cell, DM)
12. Functional abdominal pain

Question 12

What should be added to the ddx for abdominal pain if the pt is a female teen?

Answer 12

1. Ovarian cyst
2. PID
3. Mittelschmerz
4. Ectopic pregnancy

Question 13

Differential diagnosis of abdominal pain in children younger than 3 years

Answer 13

1. NEC
2. Colic
3. Midgut volvulus
4. Intussusception
5. Gastroenteritis
6. Intestinal obstruction
7. Constipation
8. UTI

Question 14

Ddx of cough

Answer 14

1. Infectious causes (URI, croup, tracheitis, bronchitis, PNA)
2. Postnasal drip from allergic rhinitis
3. Bronchospasm: asthma
4. Congenital abnormalities
5. Aspiration
6. GERD
7. Post viral infection recovery

Question 15

Ddx sore throat

Answer 15

1. Pharyngitis ( group a strep, EBV, adenovirus, coxsackie virus’s HSV, rhinovirus)
2. RPA
3. Lateral neck or para pharyngeal abscess
4. Peritonsillar abscess
5. Epiglottitis
6. Bacterial tracheitis

Question 16

Ddx of vomiting in children from birth-2 months

Answer 16

1. allergic colitis
2. Anatomical abnormalities of GI tract
3. GERD
4. Increased intracranial pressure
5. Malformation with volvulus
6. Meconium ileus
7. NEC
8. Over feeding
9. Pyloric stenosis

Question 17

Ddx vomiting age 2-5 years

Answer 17

1. Gastroenteritis
2. Intussussception
3. Posttusive
4. Head trauma
5. Brain tumor
6. DKA
7. Incarcerated hernia
8. Foreign body
9. Pyelonephritis

Question 18

Ddx vomiting age 6 years or older

Answer 18

1. Adhesions (previous surgery)
2. Appendicitis
3. Cholecystitis
4. Hepatitis
5. IBD
6. Intoxication
7. Migraine
8. Ovarian torsion
9. Pancreatitis
10. Peptic ulcer disease
11. Pregnancy

Question 19

Ddx wheezing

Answer 19

1. RAD
2. RSV bronchiolitis
3. Other infections
4. Anaphylaxis or other response to environmental allergens
5. Foreign body
6. Aspiration.
7. Congenital anomalies

Question 20

Ddx ALTE

Answer 20

1. Idiopathic
2. GERD
3. Seizure
4. Sepsis or infection
5. Cardiac disease (arrhythmia)
6. Breath holding spell
7. Upper airway obstruction
8. Metabolic disorder
9. NAT
10. Munchasen by proxy

Question 21

Ddx irritability

Answer 21

1. Infection
2. Trauma (shaken baby, subdural hematoma, fracture, corneal abrasion, hair tourniquet
3. Medications
4. colic
5. GI problems (constipation, milk protein allergy, hernia, intussuception, volvulus)
6. CNS problems (meningitis, etc)
7. Metabolic disorders
8. Toxins

Question 22

Ddx lethargy

Answer 22

1. Seizures
2. Increased ICP
3. Trauma
4. Ingestion
5. Sleep disorder
6. Infection
7. Vascular
8. Kidney or liver disorders

Question 23

Ddx ALTE

Answer 23

1. CNS (seizure)
2. Apnea of infancy/ breath holding spells
3. Metabolic
4. Cardiovascular (CHD, arrhythmia)
5. Infection (meningitis, sepsis, UTI)
6. Medications
7. GI (reflux, aspiration, intussuception, volvulus)
8. Respiratory (infection, aspiration, foreign body, airway anomaly)
9. NAT

Question 24

Ddx of bradycardia

Answer 24

1. Hypoxemia
2. Acidosis
3. Intracranial hypertension
4. Primary heart condition
5. Toxins
6. Eating disorder

Question 25

DDx chest pain

Answer 25

1. Cardiac causes (ischemia, infections, arrhythmia 2. Musculoskeletal ( muscle strain, costochondritis, trauma) 3. Respiratory. (Pna, asthma, ptx, pe) 4. GI ( gerd, FB, esophagitis) 5. Anxiety 6. Precordial catch 7. Breast disorder