DDX Flashcards
DDX Hypercalcemia (6)
- Primary hyperparathyroidism
- Increased Bone turnover
- Hyperparathyroid
- Immobilization
- Vit A intoxication- Thiazide diuretics
- Renal failure
- Familial Hypocalcuuric hypercalcemia
- Malignancy
a. Metastatic like breast Ca
b. PTH related (lung/kidney Ca)
c. Hematologic (MM, Leukemia) - Vit D related
a. Vitamin D intoxicaton
b. Granulomatous disease
i. TB
ii. Sarcoid
DDX Hypothyroidism (7)
Primary
- Thyroiditis: Hashimoto, post partum, irradiation
- Drugs: lithium, ASA, PTU
- Iatrogenic: Post ablative Graves/surgery
- Iodine deficiency
- Congenital: thryroid dysgenesis
Secondary
- Pituitary (tumor, Sheehans syndrome)
- Hypothalamic
DDX Dyslipidemia (8)
Primary
1. Genetic causes (Familial Hypercholesterolemia, Familial Combined Hyperlipidemia)
Secondary
- Obesity/Metabolic syndrome
- Diet
- Alcohol -elevated TGs
- Diabetes Mellitus
- Hypothyroidsim
- Chronic liver disease
- Monoclonal gammopathy
- Drug induced
DDX Thrombocytopenia
- Pseudothrombocytopenia
a. Platelets clumped in vial due to inadequate coagulation; repeat in Na citrate/heparin
b. Dilutional-massive RBC transfusion without PLT replenishment; pregnancy. - Decreased production:
a. Aplasia -aplastic anemia
b. Infiltration -carcinoma, lymphoma, leukemia, fibrosis
c. Toxins-drugs (gold, EtOH, TMP-SMX)
d. Infection (rubella, HIV)
e. Ineffective megakaryopoesis -Bl2/folate deficiency, myelodysplasia, EtOH - Increased destruction:
a. Immune -autoantibodies (ITP, SLE, some lymphomas), drug antibodies (quinidine, heparin, penicillin), infections (EBV, malaria, gram negative septicemia, HIV), suspected drug antibodies (thiazides, ASA, phenytoin), post-transfusion
b. Nonimmune -DIC, pre-eclampsia, vasculitis, TTPIHUS
c. Sequestration -Hypersplenism [Splenomegaly alone may dccrease pIt to 40 000 max. If lower, look for concomitant defects in production/destruction (lymphoma, autoimmune dz)]
DDX Meningitis
Meningeal Disorders
• Other infectious meningitides -CSF makes dx
o Aseptic (viral) -enteroviruses, mumps, CMV, HSV II, adenovirus, HIV
o Syphillis
o Fungal
o TB
• Meningeal neoplasm-neoplastic cells in CSF
• SAH
Parenchymal Disorders • Viral encephalitis o Often co-exists with viral meningitis o Etiologies-arboviruses (mosquitoes), HSV I, HZV, EBV, rabies • Brain abscess • Cerebral toxoplasmosis • Bacterial endocarditis • Toxic/metabolic encephalopathies • Lyme Disease • Post-infectious encephalomyelitis
DDX Acute renal failure
Prerenal
- Absolute decrease in effective blood volume
a. Hemorrhage
b. Bums
c. Gl loss/Diarrhea - Relative decrease in blood volume
a. CHF (low cardiac output)
b. Sepsis
c. Liver failure/ Cirrhosis
d. Third spacing - Disordered autoregulation
a. Meds: NSAIDs, ACEls/ARBs, Calcineurin inhibitors (cyclosporine, tacrolimus)
b. Hypercalcemia
Renal
- Vascular
a. Vasculitis (Post -infectious, Wegener’s, PAN, HSP, etc.)
b. Malignant HTN
c. Thrombotic microangiopathy
d. Cholesterol emboli
e. Large vessel disease - Glomerular
a. Acute glomerulonephritis (Post-infectious, Anti-basement membrane) - Tubular
a. Acute tubular necrosis (Ischemic vs Nephrotoxic)
b. Exogenous: Aminoglycosides, Amphotericin B, Dyes, NSAIDs, ACEIs
c. Endogenous: Hemoglobinuria, fuyoglobinuria, myeloma, uric acid, oxalate
Postrenal (especially if solitary kidney)
- Neurogenic
- Anatomic
a. Ureter -Stones, Strictures
b. Bladder -Prostatic hypertrophy, Bladder CA
c. Urethra
** 70 -75% of cases are due to Prerenal and ATN
Precipitants/causes of DKA (7)
- Infection
- Infarction (stroke, MI)
- Ischemia
- Intra-abdominal (appendicitis, cholecystitis, peritonitis, pancreatitis)
- Iatrogenic (steroids, insulin dose)
- Incision
- Intoxication (ETOH, or other drugs)
- Initial presentation
- Insulin - Non compliance
DDX urethral discharge men (4)
- Neisseria Gonorrhea
- Chlamydia
- Non gonococcal urethritis (Chlaymydia)
- Syphilis
Causes of Urinary retention
Anatomic
1. Prostate: BPH, prostatitis, prostate Ca
2. Urethra: stricture/scarring, trauma
3. Other: Cystocele, fecal impaction, stone
Neurologic
4. Hypotonic bladder – DM, sacral cord lesions, spinal shock, disc herniation
5. Detrusor sphincter dysynergy – MS, suprasacral spinal cord lesions
6. Cauda Equina
Medications
7. Anticholinergic
8. Psychtopics
9. Narcotics
Infection
10. Infection: UTI can present as retention and overflow incontinence in elderly
Causes of Hematuria (10)
Hint: approach most common then Anatomic
Tumor, infection, Trauma, Stones
Peds: think GN and congenital anomalies
Pseudohematuria
- Dyes (beets, juices)
- Hemoglobin
- Myoglobin
- Drugs (Rifampin)
- Porphyria
- Menses
Pre-renal
7. Bleeding d/o, Anticoagulants, Sickle cell,
Tumor, infection, Trauma, Stones (Renal, ureter, bladder, urethra)
Renal 1. Trauma 2. Stones 3. Carcinoma (RCC, TCC) 4. Wilms Tumor 5. Pyelonephritis 6. Glomerulonephritis 7. Intersitital Nephritis 8. Tuberculosis 9. PCOS 10. Arteriovenous malformation Ureter 11. Stone 12. Tumor Bladder 13. Cystitis 14. Tumor 15. Stones 16. Polyps Urethral 17. Urethritis 18. Stones 19. Tumors 20. Urethral stricture 21. Granuloma
DDX unconscious patient
Drugs
- ETOH
- Toxins
- Amphetamines, Opiods, cocaine, TCA, OD’s
- Withdrawals
Infection
- Meningitis
- Encephalitis
- Sepsis
Metabolic
- Electrolytes (K, Na, Ca)
- TSH – thyrotoxicosis
- Adrenal insuff
- Hypoglycemia
- Hypoxia
- Hypercarbia
- Uremia
Structural
- Seizure
- Trauma (EDH, SDH, SAH, diffuse axonal injury, bilat cortical injury)
- SAH (non-traumatic)
- ICH
- Mass/ Incr ICP
- MI
Name 10 things that are dangerous causes of HA that dont show on CT
- CO poisoning
- Temporal arteritis
- Acute angle closure
- Cerebral venous thrombosis
- Cerebellar stroke
- Early stroke
- Late >6hr SAH
- Sential HA prior to index SAH
- Meningitis
- Encephalitis
- Optic neuritis
Causes of Parkinsonism (6)
- Drug induced (antipsychotics, antiemetics)
- Toxins: CO, organic solvents
- Head trauma
- Tumor
- Any brain lesion affecting striatonigral circuits
- Metabolic: hypoparathyroid, wilsons
- Infectious: Syphilus, Toxoplasmisos, prion disease
DDX Back pain (10)
- Trauma
- Cauda equina
- Cord compression (tumor, mass)
- Cancer, MM
- Discitis
- Osteomyelitis
- Epidural abcess
- Spinal stenosis
- Sciatica
- Spondylarthropathies (ankylosing spondylitis, reactive arthritis, enteropathic spondylitis)
- Ao Dissection
- AAA
- Pyelonephritis, renal colic, pancreatitis
What toxic ingestion can be diaylzed?
ISTUMBLE Isopropanol and other BBs (AANTS) Salicyclates Theophylline Uremia Methanol Barbituates (phenobarbitol) Lithium Ethylene glycol
They have to have low protein binding, low molecular weight and water soluble (stays in blood) and low volume of distribution
DDx of hyperthermia?
DINEEO Drugs - cocaine - sympathemetics (amphetamines) - withdrawal sydromes - Neuroleptic malignant syndrome - Serotonin syndrome - Anticholinergic syndrome - Malignant hyperthermia
Infections
- Meningitis
- Encephalitis
- Abscess
- Sepsis
- Typhoid, Malaria
Neurological
- Hypothalamic stroke
- Status epilepticus
- Cerebral hemorrage
Environmental
- Heat, humidity
Endocrine
- Pheochromocytoma
- Thyroid storm
- DKA
Oncologic
- Lymphoma, Leukemia
Ddx Non-AG metabolic acidosis?
HARDUP
or GI loss vs. Renal loss
Hyperalimentation - TPN
Acetazolamide
Renal tubular acidosis (Type I = distal, Type II = proximal, Type IV = hyporeninemic hypoaldosteronism)
Diarrhea
Uretosignmoid fistula (colon will waste bicarbonate)
Pancreatic fistula (because of alkali loss - the pancreas secretes a bicarbonate rich fluid)
Ddx High AG metabolic acidosis?
MUDPILES Methanol Uremia DKA Paraldehyde/propylene glycol Infection, Iron, Isoniazid Lactate Ethylene glycol
Ddx High Osmolar Gap?
MAEDIE Methanol Acetone Ethanol Diuretics (mannitol, sorbitol) Isopropanol Ethylene glycol
Ddx VT (4)
- ACS
- Scarring (old infarct)
- Electrolytes (K, Ca, Mg)
- Hypoxia
DDx of Sick neonate (9)
Sepsis, Sepsis, Sepsis
T-Trauma (nonaccidental and accidental)
H-Heart disease/hypovolemia/hypoxia E-Endocrine (congenital adrenal hyperplasia, thyrotoxicosis)
M-Metabolic (electrolyte imbalance)
I-Inborn errors of metabolism: Metabolic emergencies
S-Sepsis (meningitis, pneumonia, urinary tract infection)
F-Formula mishaps (under- or overdilution) I-Intestinal catastrophes (volvulus, malrotation, intussusception, necrotizing enterocolitis) T-Toxins/poisons
S-Seizures
Causes of Afib (10)
- PE
- Ischemia
- Resp Dz - COPD
- Atrial enlargement
- TSH
- ETOH
- Sepsis
- HTN Cardiomyopathy
- Valvular dz
- CHF
- SSS
- Myocardial contusion
- Cardiac surgery
- Catecholamine excess
- Accessory pathway - WPW
Ddx Microcytic anemia (5)
- Fe Def anemia
- Thalassemia
- Anemia of Chronic dz
- Lead poisoning
- Sideroblastic anemia
Ddx Syncope (10)
R/O seizure
- Neurologic:
- Seizure
- Stroke
- Vasovagal
- Situational syncope
- Orthostatic HypoTN
- Carotid sinus sensitivity
- Autonomic neuropathy - Cardiac:
- Tachy or brady arrhythmia
- AoStenosis
- MI
- HOCM
- Cardiac Tamponade
- Atrial myoma
- Aortic dissection
- WPW, ARVD, AVB, - Pulmonary
- PE
- Hypoxia
- Hypercapnia - Non-cardiac:
- hypovolemia
- Drugs (ccb, bb, vasodilators, diuretics)
- Autoimmune insuff (DM, AI, spinal cord lesion),
- Hypoglycemia
- Narcolepsy
- Vertigo
Ddx Abdominal pain in peds (10)
- Pyloric Stenosis
- Malrotation
- Mid gut volvulous (commonly rotates around SMA causing ischemia)
- Appendicitis
- Intusseception
- Duodenal Atresia
- Mesenteria adenitis
- Constipation
- Referred pain from pneumonia, UTI, Renal colic (RLL can mimic appy)
- Gastroenteritis
- PUD
- DKA
- Henoch-Schnlein purpura
- Testicular Torsion (Check cremaster reflex) 15. Renal colic
Ddx normocytic anemia (3)
- Anemia chronic disease
- Hemolytic anemia
- Acute hemorrage
- Myelodysplasia
- Infiltration (leukemia, myeloma, mets, infection)
- Aplasia
- Liver Dz
- Uremia
- Hyper/Hypothyroid
- Treated nutritional def
Ddx macrocytic anemia (3)
- Folate or B12 def
- Reticulocytosis
- ETOH
- Liver Dz
- Myelodysplasia
- Drugs
Ddx Isolated elevated INR/PT? (3)
- Warfarin
- Vitamin K def
- Liver Disease
- Factor 7 def (inherited)
- Factor 7 inhibitor
Ddx Elevated PTT (3)
- Heparin
- Hemophilias
- vWF
Ddx Elevated INR and PTT (3)
- Heparin and Warfarin
- DIC
- Liver disease
- Deficiencies of prothrombin, fibrinogen, Factors V and X
Ddx agitated delirium (10)
DIMS
DRUGS
1. Sympathemimometics/Stimulants: - Cocaine, amphetamines, methamphetamines - PCP, ketamine
2. Anticholinergics - Serotonin Syndrome - Sedative withdrawl syndrome
INFECTION
3. Viral or bacterial meningitis, encephalitis
METABOLIC/Endocrine
- Hyponatremia, Hypercalemia
- Hypoglycemia
- Hypoxia
- Uremia
- Hyperammonia
- Thyrotoxicosis
STRUCTURAL
- Trauma
- Stroke
- Hemorrhage
- Mass
Ddx Fever in returning traveller (10)
- Malaria
- Typhoid
- Dengue Fever
- Meningitis
- Rickettsial disease
- Mononuecleosis (CMV, EBV)
- Yellow Fever
- Lassa Fever
- Japanese encephalitis
- Cysteriosis
- Viral hemorragic fevers
- Common infections (pnuemonia, UTI, gastroenteritis)
- Hepatitis A,B,C
- HIV
- STIs- do GU exam
Ddx Vertigo (8)
- Cerebellar stroke
- Vertebrobasilar a. Insufficiency
- Vertebral artery dissection
- Multiple sclerosis
- BPPV
- Vestibular neuritis
- Labyrinthitis
- Ménière’s disease
Ddx acute painful vision loss (5)
- Acute angle closure glaucoma
- Optic neuritis
- Trauma
- Uveitis
- Temporal arteritis
- Keratitis
Ddx painful red eye (8)
- Acute angle closure glaucoma
- Keratitis ( UV or ulceration)
- Epi scleritis
- Uveitis
- Scleritis
- Enopthalmitis
- Conjunctivitis
- Orbital cellulitis
Ddx acute painless vision loss (8)
- Central retinal artery occlusion
- Central retinal vein occlusion
- Retinal detachment
- Temporal arteritis
- Amaurosis fugax (TIA)
- Vitreous hemorrage
- Macular degeneration (more insidious)
- Optic neuritis (MS)
- Papilledema
- Opthalmic migraine
- Vitreous detachment
Ddx hypertensive emergencies with ‘toxicologic’ characteristics (5)
- Drug/Sympathomimetic OD
- Anti-cholinergic
- MAOI toxicity
- Methylxanthine toxicity
Non-toxicologic causes
- Environmental hyperthermia
- Febrile illness
- Pheochromocytoma
- Carcinoid syndrome
- Thyroid Storm
- Meningitis
Ddx Pinpoint pupils
- Opiod overdose
- Central pontine stroke (hemorrhage)
- Organophosphate
- Cholinergic syndrome (organophosphates)
- Neurosyphilis apparently..
- Pilocarpine drops..
Ddx of Hyperkalemia (7)
- Pseudohyperkalemia (due to hemolysis)
- Decreased excretion
- Renal failure
- Renal secretory defects (interstitial nephritis, sickle cell) - Hypoaldosteronism: hyporeninism (type IV RTA)
- Adrenal insuff
- Drugs (spironolactone, Acei, NSAIDS)
- K shift out of cells
- Burns
- Rhabdomyalysis
- Hemolysis
- Severe infection
- Metabolic acidosis
- Insulin deficiency - Hyperkalemic periodic paralysis
- Drugs (digitalis toxicity, beta-adrenergic antagonists, suxx)
- Iatrogenic
Ddx Bitemporal hemianopsia (3)
- Pituitary tumor
- Craniopharyngioma
- Meningioma
- Aneurysm of circle of willis
- Metastatic carcinoma
Ddx Dyspnea (10)
CV
- MI
- CHF
- Tamponade
Pulmonary
- PTX
- Asthma
- COPD
- Pneumonia
- PE
- Aspiration
- Anaphylaxis
- Anemia
- Acidosis
Ddx Hemoptysis (10)
- Malignancy
- Bronchiectasis
- Lung abcess
- Pulmonary AVM
- CHF
- Alveolar hemorrhage syndrome
- Infection
- Bacterial
- Viral
- TB
- Fungal Inflammation - SLE
- Goodpastures syndrome
- Wegeners Granulomatosis
DDX intraocular HTN (>20mmHg) (3)
- Glucoma
- Suprachoroidal hemorrage
- Retrobulbar space occupying tumor
Ddx Drug induced hyperthermia (7)
- Malignant hyperthermia
- NMS
- Psychostimulants (cocaine, amphetamines,MDMA)
- Anticholinergic toxicity
- Serotonin syndrome
- Salicyclate poisoning
- Withdrawal syndromes (last 2 are more fever than hyperthermia)
Ddx severe HA (10)
- SAH/ICH
- Sub-dural hemorrage
- Temporal arteritis
- Meningitis
- Migraine
- Acute angle glucoma
- Cerebral venous thrombosis
- CO poisoning
- Preeclampsia
- Brain Tumor/ Increased ICP
- Idiopathic intracranial HTN
- Pseudotumor cerebri
Ddx Rash on palms and soles (6)
- Syphilis (secondary)
- Erythema multiforme/SJS (Drug rxn)
- Hand, foot, mouth dz (Coksakie virus)
- Rocky Mountain spotted fever
- Kawasaki’s
- Atypical Measles
- Toxic Shock syndrome
- Meningococcemia may cause petichiae on the palms and soles.
- Bacterial endocarditis with it’s Janeway lesions and Osler’s nodes.
- Scabies
- Tinea mannum
- Atopic dermatitis
Ddx penile ulcer (3)
- Syphilis
- Herpes Simplex
- Chancroid
- Lymphogranuloma venereum
- Bechet’s syndrome
- Neoplasm
- Lichen Planus
Ddx Fever and ALOC
- Infection
- Sepsis
- Meningitis
- Encephalitis
- Abcess
- Tetanus
- Typhoid
- Malaria - Drug/Toxin
- Psychostimulants(cocaine, amphetamines, MDMA)
- Malignant hyperthermia
- NMS
- Anti-cholinergic syndrome
- Serotonin syndrome
- Salicyclate toxicity
- Withdrawal syndromes - Neurologic
- Hypothalamic stroke
- Status Epilepticus
- Cerebral hemorrage - Environmental
- High temperature or humidity Endocrine
- Thyroid storm
- Pheochromocytoma
- DKA - Oncologic
- Lymphoma
- Leukemia
Ddx ALOC (AEIOUTIPS)
A — Alcohol/Acidosis E — Endocrine Epilepsy Electrolytes (Na, K, Ca) I — Infection (Meningitis, Sepsis)/Insulin O — Oxygen, Opiates, Overdose U — Uremia T — Trauma/Toxins/Temperature I — Insulin/Infection P — Poisoning/Psychosis S —Stroke/Seizure/Space occupying lesions
Or
DIMS
Or
Diffuse/Metabolic processes vs. Focal/ structural
4 categories of causes of mesenteric ischemia
- Arterial mesenteric embolus (usu cardiac in origin)
- Arterial mesenteric thrombus
- 2ndary to atherosclerotic dz. - Venous mesenteric thrombus (least common) usu SMV
- Thrombotic d/o (Factor V leiden, protein c/s, AT III)
- Hypercoagulable state
- Sickle cell crisis - Polycythemia - Non-occlusive
- Hypovolemia/Shock
- Pancreatitis
- Sepsis
- Drugs causing vasoconstriction
Ddx Vesiculobullous Rash (name 5, there are 10)
- Herpes
- Varicella
- Dyshidrotic eczema
- EM Major
- SJS/TEN
- SSSS
- TSS
- P. vulgaris
- Meningococcemia/gonococcemia
- Nec Fasc
Ddx Rash and joint pain (5)
- HSP
- Rockymountian spotted fever
- Lyme Disease
- Reactive arthritis/Reiter’s
- Transient synovitis
- Drug Reactions – including SJS/TEN
- Rheumatic illnesses (SLE, IBD, Psoriatic, JIA, Ank spond…)
- Dermatomyositis
- Septic joint + sepsis
Ddx strawberry tongue (3)
- Kawasaki
- Scarlet fever
- TSS/STSS
Ddx delirium (iwatchdeath)
I - Infectious:
Sepsis, encephalitis, meningitis, syphilis, central nervous system abscess
W -Withdrawal: Alcohol, barbiturates, sedative-hypnotics
A- Acute metabolic: Acidosis, electrolyte disturbance, hepatic or renal failure, other metabolic disturbances (↑ or ↓ glucose,magnesium, calcium)
T - Trauma Head trauma, burns
C- CNS disease: Hemorrhage, stroke, vasculitis, seizures, tumor
H- Hypoxia: Acute hypoxia, chronic lung disease, hypotension
D- Deficiencies: Vitamin B12, hypovitaminosis, niacin, thiamine
E- Environmental: Hypothermia, hyperthermia, Endocrinopathies (diabetes, adrenal, thyroid) A- Acute vascular: Hypertensive emergency, subarachnoid hemorrhage, sagittal vein thrombosis
T- Toxins or drugs Medications, street drugs, alcohol, pesticides,industrial poisons (e.g., carbon monoxide, cyanide,solvents)
H - Heavy metals Lead, mercury
Ddx ring enhancing lesion on CT with contrast (8)
DRMAGICL D - demyelinating disease (incomplete ring) R - radiation necrosis or resolving haematoma M - metastasis A - abscess G - glioblastoma multiforme I - infarct (subacute phase) C - contusion L - lymphoma
Ddx asterixis (3)
- Hepatic encephalopathy
- Hypercarbia
- Uremic encephalopathy
DDX/ Great imitators of ruptured AAA
- when you diagnose these, think AAA…
- Renal Colic
- Diverticulitis
- ACS
- Perforated viscous
- Bowel obstruction
- Pancreatitis
- Intestinal ischemia
- Cholecyctitis
- Appendicitis
- MSK back pain
DDx Diplopia
Monocular:
- Refractive error
- Cataract/lens dislocation
- Corneal scarring
Biocular
- NM junction
- MG - Extra-ocular muscle restriction/entrapment
- Orbital inflammation
- Orbital tumor
- Orbital Floor Fracture - Neuronal
- Ischemia
- DM
- Aneurysm
- Tumor
- Graves opthalmopathy
Complete CN 3 palsy - BAD
CN 6 palsy - R/O incr ICP
CN 4 palsy
