21 results
CNS Ring-Enhancing Lesions - Immunocompromised vs Immunocompetent
Multiple Ring-Enhancing Lesions:
 • Toxoplasmosis (CD4 < 100)
 • Other
lesions • 80% with lung ... multiple lesions Infectious ... Lesions #Brain #differential ... #diagnosis #causes ... #radiology #neurology
CNS Ring-Enhancing Lesions - Differential Diagnosis
 • Infections: Cerebral abscess (bacterial, fungal, parasitic), Neurocysticercosis, Tuberculoma, Cerebral
Lesions - Differential ... Diagnosis • Infections ... Malignancy: Metastases (lung ... Demyelinating Disease ... #Diagnosis #neurology
Chronic Cough - Differential Diagnosis Algorithm
Red Flags:
 • Fever, night sweats, chills (infection)
 • Weight loss,
sweats, chills (infection ... Dyspnea (underlying lung ... refer + order CT ... History of cancer, lung ... Diagnosis #Algorithm #causes
Lung Abscess - Diagnosis and Management Summary

Lung Abscess Etiology:
 • Necrosis of lung parenchyma by a
polymicrobial infection ... • Most common cause ... seen • Chest CT ... Abscess Differential ... #causes #management
Back Pain - Differential Diagnosis
Primary Back Pathology:
 • Musculoligamentous injury (a.k.a. lumbosacral strain)
 • Spondylosis (i.e.
Manifestations: • Infection ... (most common: lung ... (most common: lung ... , Aneurysm • Pancreas ... #Diagnosis #causes
Bronchiectasis - Permanent dilation of an airway
WHAT CAN YOU SEE ON CT?
1) Lack of tapering of
CAN YOU SEE ON CT ... involving both lungs ... Immunodeficiency 3) Infection ... Rheumatologic/Autoimmune diseae ... pulmonary #diagnosis #differential
Common Variable Immunodeficiency (CVID)

What?
CVID: Immunodeficiency disorder with hypogammaglobulinemia -> increased infection risk secondary to impaired B-cell
• Chronic lung ... lymphocytic interstitial lung ... Chest CT: • Ground-glass ... and M panel Management ... DDX - Other causes
Nontuberculous Mycobacteria (NTM) Infections 

Mycobacterial species other than those belonging to the Mycobacterium tuberculosis complex and
status • Chronic lung ... status NTM Cause ... Lungs: • 90% ... Imaging, high res CT ... #differential #
CNS Infection in HIV / AIDS - Differential Diagnosis Framework

Principles of HIV-Associated CNS Opportunistic Infections:
 •
CNS Infection in ... enhancement on CT ... Demyelinating disease ... caused by the JC ... #Infections #differential
Lung Infections in HIV - Differential Diagnosis Framework

Disease by CD4 Count:
Any CD4 Count:
 • Mycobacterium tuberculosis,
Lung Infections ... in HIV - Differential ... • CT: Halo sign ... Lymphadenopathy, CNS ... factor • May cause