Infectious Diseases Part 2

Question 1

Regarding Candidiasis, what is shown on a Potassium Hydroxide (KOH) Smear

Answer 1

Budding yeast and pseudohyphae

Question 2

Symptoms of Candidiasis in the oropharyngeal cavity (Thrush)

Answer 2

-friable, white plaques that leave erythema if scraped

Question 3

Treatment for Thrush

Answer 3

• Nystatin swish and swallow

- Clotrimazole troches

Question 4

Intertrigo is a cutaneous infection that is most common in moist, macerated areas. The rash appears beefy, red and distinct scalloped orders and satellite lesions. What is the treatment

Answer 4

Clotrimazole topical, keep area dry

Question 5

How is Cryptococcis transmitted?

Answer 5

Pigeon and bird droppings inhalation

Question 6

Risk factors for Cryptococcosis

Answer 6

-Most common in immunocompromised (CD4 < 100)

Question 7

Symptoms of Cryptococcosis

Answer 7

• Meningoencephalitis: headache and meningeal signs (stiff neck, nausea, vomiting, photophobia)
• Pulmonary: pneumonia
• Skin lesions if disseminated

Question 8

Diagnostics for Cryptococcosis

Answer 8

• Lumbar puncture: Fungal CSF pattern (increased WBC, decreased glucose, increased protein)
• Cryptococcal antigen in CSF on visualization with encapsulated yeast on India Ink Stain

Question 9

Treatment for Cryptococcosis

Answer 9

• Amphotericin B + Flucytosine x 2 weeks followed by Oral Fluconazole x 10 weeks
• Fluconazole if prophylaxis needed and if CD4 < 100

Question 10

What is the biggest risk factor for Histoplasmosis?

Answer 10

Immunocompromised states and people with CD4 < 150

Question 11

Transmission of Histoplasmosis

Answer 11

• Inhalation of soil containing bat and bird feces in Mississippi and Ohio River Valleys
• Demolition, Spelunkers, Excavators

Question 12

Symptoms of Histoplasmosis

Answer 12

• Asymptomatic (Most patients)

- PNA (Can Mimic TB)

Question 13

Diagnostics for Histoplasmosis

Answer 13

• CXR: Pulmonary infiltrates, hilar or mediastinal LAD
• Antigen testing: via sputum (PCR) or urine highly specific
• Cultures: Most specific test

Question 14

Treatment for Histoplasmosis

Answer 14

• Asymptomatic: No treatment needed
• Mild: Itraconazole
• Severe: Amphotericin B

Question 15

Risk Factor for Pneumocystis Pneumonia (PCP)

Answer 15

CD4 < 200

Question 16

Symptoms of PCP

Answer 16

• Classic Triad: progressive dyspnea on exertion, fever, nonproductive cough
• Oxygen desaturation with ambulation

Question 17

Diagnostics for PCP

Answer 17

• CXR: diffuse bilateral interstitial infiltrates
• Labs: Increased LDH
• Lung Biopsy: Definitive

Question 18

Treatment for PCP

Answer 18

• Bactrim drug of choice x 21 days

- If HIV +, add Prednisone if hypoxic

Question 19

If the chest xray is positive with PCP PNA, what will it show?

Answer 19

Bilateral diffuse symmetric finely granular opacities/reticular interstitial airspace disease

Question 20

PCP Prophylaxis in HIV

Answer 20

CD4 < 200: Bactrim

Question 21

Risk factor for MAC

Answer 21

CD4 < 50

-Underlying pulmonary disease

Question 22

Transmission of MAC

Answer 22

-Present in soil and water (not person to person)

Question 23

Treatment for MAC

Answer 23

-Clarithromycin + Ethambutol + Rifampin

Question 24

Prophylaxis for HIV patients against MAC

Answer 24

-Clarithromycin or Azithromycin if CD4 < 50

Question 25

Pathophysiology of TB

Answer 25

After inhalation, Mycobacterium Tuberculosis goes to alveoli, gets incorporated into macrophages, and can disseminate from there

Question 26

In chronic/latent infection, what three things do you need to show the person is not infectious with TB?

Answer 26

- Positive PPD - No symptoms of infection - No imaging findings of active infection

Question 27

With secondary/reactivation TB, what is seen on CXR?

Answer 27

Apex/upper lobes with cavitary lesions. These patients are contagious

Question 28

Regarding CXR and TB, explain the differences to each stage of TB

Answer 28

-Primary: middle/lower lobe -Reactivation: apical (upper lobe) Miliary TB: small millet-seed nodular lesions

Question 29

For sputum acid-fast staining, what must you get?

Answer 29

3 samples taken on 2 consecutive days must be negative to rule out TB

Question 30

However, for TB, what is more sensitive than sputum smears?

Answer 30

NAAT

Question 31

Management of active TB

Answer 31

Initiate 4-drug therapy: RIPE for 2 months | -Followed by 4 months of RI = 6 month total duration

Question 32

TB drugs and side effects

Answer 32

- Rifampin: orange colored secretions - Isoniazid: peripheral neuropathy, hepatitis - Pyrazinamide: hepatitis and hyperuricemia - Ethambutol: Optic Neuritis, red/green color blindness

Question 33

Treatment for Latent TB infection

Answer 33

``` -INH + Pyridoxine (Vitamin B6) x 9 months OR -RIF X 4 months OR -INH + Rifapentine x 3 months OR -INH x 6 or 9 months ```

Question 34

> 5 mm to be positive for TB:________ > 10 mm to be positive for TB: __________ > 15 mm to be positive for TB: ________

Answer 34

5: HIV or immunosuppressed, close contact with active TB, CXR with old TB 10: all other high-risk populations 15: everyone else, no risk factors for TB

Question 35

MC helminth infection in the US

Answer 35

Enterobiasis (Pinworm)

Question 36

Transmission of Enterobiasis Vermacularis

Answer 36

-Hand-mouth contact with contaminated fomites, fecal-oral contamination in school-aged children

Question 37

Symptoms of Enterobiasis

Answer 37

- Perianal itching, especially nocturnal (eggs are laid at night) - Abdominal pain, nausea, vomiting

Question 38

Diagnostic for Enterobiasis

Answer 38

-Cellophane tape test or pinworm paddle test early in AM to look for eggs under a microscope

Question 39

Treatment for Enterobiasis

Answer 39

-Albendazole, Mebendazole, or Pyrantel (in pregnancy)

Question 40

MC intestinal helminth worldwide

Answer 40

-Ascariasis (roundworm)

Question 41

Diagnostic for Ascariasis

Answer 41

-Stool ova and parasite

Question 42

treatment for Ascariasis

Answer 42

- Albendazole or Mebendazole | - Pyrantel if pregnant

Question 43

Trichinosis is transmitted through

Answer 43

Raw or undercooked meat (pork, boar, or bear)

Question 44

Adult Trichinosis are excreted in the stool and larva penetrate intestinal wall and go where?

Answer 44

Encapsulate in striated muscle tissue

Question 45

Symptoms of Trichinosis

Answer 45

- GI phase: abdominal pain, nausea, vomiting - Muscle phase: myositis (weak or painful muscles), subungal splinter hemorrhages - Cardiac: Myocarditis

Question 46

What labs are shown with Trichinosis?

Answer 46

- Eosinophilia (hallmark) | - Increased CK and LDH (due to muscle involvement)

Question 47

Treatment for Trichinosis

Answer 47

-If any CNS, cardiac, or pulmonary involvement, Albendazole or Mebendazole

Question 48

Hookworm is common in countries where Hookworm (Ancylostoma duodenale and Necator americanus)

Answer 48

Poor access to adequate water, sanitation, and hygiene

Question 49

What three conditions must be met to transmit Hookworm? (Ancylostoma duodenale and Necator americanus)

Answer 49

- Human fecal contamination of soil - Favorable soil conditions for larvae growth - Contact of human skin with contaminated soil

Question 50

4 phases of hookworm symptoms

Answer 50

- Skin: pruritic erythematous dermatitis at site or entry - Transpulmonary: asymptomatic - GI: N/v, diarrhea, GI bleed rare - Chronic Nutritional Impairment: daily loss of blood, iron, and albumin

Question 51

Treatment for Hookworm

Answer 51

- Albendazole or Mebendazole, Pyrantel | - Iron supplementation, multivitamins