POM - FUNGI and MISC

Pulmonary (Most Common): Occurs in patients with underlying lung disease (COPD, smoker).  

Chronic cough, fatigue, weight loss.  

Fever, night sweats, abd pain, diarrhea 

Imaging shows "tree-in-bud" opacities, nodules, or cavitary lesions.  

Disseminated: Severely immunocomp. (CD4 <50); fever, night sweats, abdominal pain. 

Dx requires: Sx, imaging, positive cx 

Nontuberculous Mycobacteria (NTM) / M. avium complex (MAC)

Treatment: MAC

Azithromycin (or clarithromycin) + Ethambutol + Rifampin

• Add Amikacin for severe fibrocavitary disease

Tx must be continued until negative for >12mo

If failed tx / localized disease —> Surgical resection

What do you need to monitor while treating for MAC?

• CBC, CMP

• Vision (ethambutol)

• Hearing (amikacin)

• Sputum cultures x1-2mo + CXR x6mo

Primarily affects the skin and peripheral nerves. 

From prolonged respiratory exposure, broken skin exposure, 9-banded armadillo. 

Skin: Hypopigmented or erythematous skin patches, nodules, loss of eyebrows/eyelashes (madarosis).  

Nerves: Sensory loss within lesions, enlarged/tender peripheral nerves, weakness, painless burns/wounds. 

Mycobacterium Leprae

Treatment: Leprosy (Tuberculoid type; Lepromatous type)

Tuberculoid: Dapsone + rifampicin x12 mo. 

Lepromatous: Dapsone + rifampicin + clofazimine x24 mo 

Tuberculoid Leprosy

• Pathophysiology: Characterized by a strong immune response that keeps the infection largely contained.

• Clinical Presentation: Results in limited disease with only a few skin lesions. These lesions classically present as well-defined hypopigmented patches that have sensory loss within them.

Lepromatous Leprosy

• Pathophysiology: Characterized by a weak immune response that allows the bacteria to spread systemically.

• Clinical Presentation: Results in extensive disease with numerous or diffuse skin lesions and widespread nerve involvement. Because of the severe dissemination, it may also affect other areas such as the eyes, nose, testes, and bone.

Latent: No active disease; cannot transmit.  

Active: Slowly progressive constitutional symptoms (fever, night sweats, weight loss) and chronic cough (dry → purulent or blood-streaked ;  (can cause life-threatening hemoptysis).  

PE: Chronically ill and malnourished appearance,  

post-tussive apical rales. CXR no specific features. 

Tuberculosis

Gold standard diagnostics for tuberculosis

3 consecutive morning sputum, x8 hr  

Cx is gold standard (6-8wk) 

Imaging findings for tuberculosis

Ghon complex/focus (calcified primary focus) or Ranke complex (+ lymph node)

Treatment: Tuberculosis (Latent, active, monitor, prevention, side effects)

Latent (3 different regimens):

• Isoniazid + Rifapentine weekly x3mo (3HP)

• Rifampin daily x4mo (4R)

• Isoniazid + Rifampin daily x3mo (3HR)

Active: RIPE Therapy

• First 2 months: Rifampin, Isoniazid, Pyrazinamide, Ethambutol

• Next 4 months: Rifampin + Isoniazid

Monitor:

• Monthly F/U

• LFTs

• Sputum culture until conversion to latent

Drug Resistant types: RR-TB (rifampin), MDR-TB (Isoniazid + Rifampin), XDR-TB (MDR +RR)

Prevention: BCG vaccine

Pt EDU: Emphasize adherence + Side effects

• Isoniazid —> Peripheral neuropathy

• Rifampin —> OCPs + orange secretions

• Ethambutol —> Optic neuritis (reversible with d/c) + Red/green color discrimination and visual acuity defects

Diagnose and Treat:

White, curd-like plaques on an erythematous base that are usually painless and can be wiped away.

Dx: Oral Candidiasis

Tx: Nystatin suspension, Clotrimazole troches, or Fluconazole.

• Treat dentures and improve oral hygiene. 

! Evaluate for underlying immunodeficiency if recurrent ! 

Diagnose and Treat
Odynophagia, dysphagia, and retrosternal chest discomfort. Considered an AIDS-defining illness. 

Diagnostics: Endoscopy +/- biopsy 

Dx: Esophageal Candidiasis

Tx: Oral Fluconazole (IV if unable to tolerate PO)
! Evaluate for underlying immunodeficiency if recurrent ! 

Candida enters the bloodstream (candidemia) or deep tissues (eyes, kidneys, abdomen).  

Presents with persistent fever, sepsis, or septic shock. 

Invasive candidiasis

Treatment: Invasive candidiasis

First line: IV echinocandin (caspofungin, micafungin, anidulafungin)

Step-down: fluconazole

! High mortality if left untreated !

Diagnose and Treat:

Often asymptomatic, but may resemble a UTI. 
Diagnostics: Candida in UA or Urine Cx  

Dx: Candiduria (Funguria)

Tx:

1. Differentiate if colonization or infection

2. If infection (symptomatic) —> Fluconazole

Opportunistic fungal infection latent in alveoli.  

Subacute interstitial pneumonia.  

Progressive dyspnea, nonproductive cough, fever, and hypoxia (often worse with exertion).  

Sx may appear more severe than PE findings. 

Pneumocystitis Jirovecii Pneumonia (PJP)

Diagnostic test for Pneumocystis jirovecii Pneumonia (PJP)

Bronchoalveolar lavage (BAL), CT, CXR

Treatment: Pneumocystis Jirovecii Pneumonia (PJP) (First-line, mod-severe, prevention, prognosis)

First-Line: TMP-SMX 14-21d (start empiric therapy if suspected clinically)

Mod/Severe: Add corticosteroids (with significant hypoxemia)

Prevention: TMP-SMX when CD4 <200

Prognosis: 100% fatal if no early/adequate tx; recurrence is common

Found in Mississippi/Ohio River Valleys and Great Lakes (soil disruption). 50% asympt. 

Often affects immunocompetent individuals.  

Pulm: Fever, cough, dyspnea.  

Disseminated: Skin is the MC extrapulmonary site (verrucous or ulcerative lesions). 

Blastomycosis

Treatment: Blastomycosis

Mild/Mod (pulmonary): Itraconazole

Severe (Pulm, CNS, Dissemination): Amphotericin B

Found in Ohio/Mississippi River Valleys (bat/bird droppings/caves).  

Acute pulmonary mimics TB (MC symptomatic form). Progressive Disseminated (Highest risk: HIV/AIDS): Fever, weight loss, hepatosplenomegaly, and oral/pharyngeal ulcers
CXR: miliary pattern in disseminated disease

Histoplasmosis (Histoplasma capsulatum)

Treatment: Histoplasmosis (Mild/mod, severe, AIDS)

Mild/Mod (pulmonary): Itraconazole

Severe (Disseminated): Amphotericin B, then transition to Itraconazole

AIDS: may require chronic suppression

What is the MCC of fungal meningitis?

Cryptococcosis

Inhaled from dried bird droppings; primarily affects advanced HIV/AIDS patients.  

CNS Disease: HA, fever, AMS, cranial nerve deficits, and elevated ICP. 

Rales/crackles, nuchal rigidity, papilledema, pustules 

Diagnostics: Serum Ag, CSF (most sensitive), LP (confirms), CXR/CT (solitary nodule/mass/infiltrate) 
MRI brain (______omas / hydrocephalus bec ICP) 

Cryptococcosis

Treatment: Cryptococcosis (Mild/mod, ssevere, HIV/AIDS)

Mild/Mod (Pulmonary): Fluconazole x6-12mo

• Alts: Itraconazole, voriconazole, posaconazole, isavuconazole

Severe (Pulm, CNS, Disseminated): Amphotericin B + Flucytosine $$
MGMT of ICP (Critical): Frequent LPs or ventricular shunt

HIV/AIDS: Long-term fluconazole until immune recovery on ART

AKA "Valley Fever" found in desert soil of the Southwestern US (AZ, CA).  

Pulmonary sx plus extrapulmonary disease: Arthralgias ("desert rheumatism"), erythema nodosum (on shins), skin lesions, meningitis, rales/crackles

Coccidiodomycosis

Treatment: Coccidiodomycosis (Mild, Mild with RF, Severe)

Mild (Immunocompetent): No tx

Mild w/ RF or Mod: Fluconazole or Itraconazole (6-12wk)

Severe: Amphotericin B + triazole (Fluconazole) then transition to fluconazole monotherapy 12-24wk

Occurs primarily in patients with asthma or cystic fibrosis. Asthma exacerbations, wheezing, eosinophilia and elevated IgE. 

ABPA (Aspergillosis)

Treament: ABPA (Aspergillosis)

First-line: Chorticosteroids

± Itraconazole to reduce fungal burden (remember it’s an allergy not invasive infection)

Note: everyone is exposed, but not everyone gets the disease

Fungus ball colonizing a preexisting lung cavity

Often asymptomatic, but hemoptysis is the classic finding d/t irritation of blood vessels. 

Aspergilloma (Aspergillosis)

Treatment: Aspergilloma (aspergillosis) (Asympt, Hemoptysis)

Asymptomatic: Observation

Significant hemoptysis: Surgical resection

Occurs in severe neutropenia or severely immunocompromised patients.  

Severe pulmonary infection and dissemination.  

CT shows classic halo sign (solid area with puff) 

Invasive Aspergillosis

Treatment: Invasive Aspergillosis (First-line, +severe)

First-line: Voriconazole

• Add echinocandin in severe disease (broader spectrum)

Misfolded proteins causing neurodegeneration. Rapidly progressive dementia (weeks to months), myoclonus, ataxia, dysarthria, hypokinesia. 

Progression to akinetic mutism and coma.  

MRI: Cortical ribboning and basal ganglia hyperintensity ; CSF, EEG 

Prion Disease (CJD)

Treatment: Prion Disease (CJD)

No curative treatment, fatal within 1 yr

Endemic travel history. Cyclic fevers with chills and sweating, headache, fatigue, abdominal pain.  

Severe Disease (P. falciparum): Anemia, cerebral malaria (AMS, seizures), acute kidney injury, respiratory distress, splenomegaly. 

Diagnostics: Thick (detect falciparum ring) and Thin (species) Giemsa-stained blood smears 

Malaria

Treatment: Malaria (Uncomplicated, Severe, Prognosis, Chemoprophylaxis)

Uncomplicated: Artemisinin-based combination therapy (ACT) (First-line for P.falciparum)

Severe: IV artesunate followed by oral therapy

Prognosis: Sx improvment in 48-72hr

Chemoprophylaxis:

• Atovaaquone-proguanil

• Doxycycline

• Mefloquine

• Chloroquine

*Note: sickle cell provides partial protection against severe P.falciparum

Contracted from cat feces or undercooked meat.  

Immunocompetent: Asymp or mono-like illness 

Congenital: Miscarriage, severe neonatal disease.

• Ocular: Retinochoroiditis (visual changes, eye pain, photophobia).

  • MC in late manifestation of congenital. 

Reactivated (AIDS): Causes encephalitis (fever, AMS, focal neuro deficits); MRI shows multiple ring-enhancing brain lesions. 

Toxoplasmosis

What is the most common late manifestation of congenital toxoplasmosis?

Retinochoroiditis (visual changes, eye pain, photophobia)

Treatment: Toxoplasmosis (Mild/immunocompetent, severe/preg/immunocomp, AIDS prophylaxis)

Mild/Immunocompetent: No tx

Severe / Pregnant / Immunocompromised: Pyrimethamine + Sulfadiazine + Folinic acid

Retinochoroiditis: self-limited

Prophylaxis in HIV (CD4 <100): TMP-SMX

Fecal-oral.

RF: crowding, poor sanitation, malnutrition 

Diarrhea progressing to dysentery (bloody diarrhea) and abdominal cramping.

Extraintestinal spread results in a liver abscess. 

Stool test: Trophozoites containing ingested RBCs 

Entamoeba Histolytica (Amebiasis)

Treatment: Entamoeba Histolytica (Amebiasis)

Tissue Amebicide (Metronidazole or tinidazole) AND luminal agent (paromomycin, iodoquinol, or diloxanide)

If Liver abscess —> IV metronidazole ± needle aspiration if large

Thrives in warm freshwater (lakes, 21% neti pots). Severe HA, high fever, meningismus, rapid progression to seizures and coma. Death usually occurs within a week. 

Naegleria fowleri (Free-living amebae)

Treatment: Naegleria fowleri (Free-living amebae)

1. Miltefosine (antiparasitic)

2. Combos of amphotericin B, azoles, azithromycin, and rifampin

3. Contact CDC

Opportunistic, typically affecting immunocompromised hosts. Mimics a space-occupying lesion (AMS, HA, stiff neck, hemiparesis), cranial nerve palsies. Cutaneous ulcers in AIDS patients. 

Extensive diagnostic evaluation +/- CSF, CT (can mimic toxoplasmosis) 

Acanthamoeba (Free-Living Amebae)

Treatment: Acanthamoeba (Free-living amebae)

Miltefosine + combination therapy. 

Diagnose and Treat:

Corneal infection frequently associated with contact lens wear. Presents with pain out of proportion to exam. Exam shows indolent corneal ulceration and stromal ring. 

Dx: Acanthamoeba Keratitis

Tx: Consult ophthalmology immediately

AKA "Beaver Fever" (wilderness water, daycares). Acute phase: watery diarrhea.  

Chronic phase: Greasy, foul-smelling, frothy stools with no blood or pus and weight loss. 

Diagnostics: Stool Ag testing (preferred),  

   Stool microscopy: trophozoites (w/o ingested RBCs) 

Giardiasis

Treatment: Giardiasis

Metronidazole (5-7d) or Tinidazole (single-dose)

Diagnose and Treat:
MC helminth infection in U.S.  

Severe itching around the anus and perineum, restless sleep ("Nocturnal perianal pruritis"). 

Exam: perianal excoriations 2° skin infections 

Diagnosed via Scotch tape test. 

Dx: Enterobius vermicularis (pinworms)

Tx: Albendazole or mebendazole

• repeat dose in 2 weeks d/t requent reinfection + treat family members / close contacts

Other name for pinworms

Enterobius Vermicularis

Other name for tapeworms

cestoda

Tapeworms from fish

T.saginata

Tapeworms from pork ; implicated in neurocysticercosis (seizures, intracranial lesions)

T.solium

Tapeworm from fish ; may cause vitamin B12 deficiency

D. latum

Treatment: Tapeworms (cestoda)

Praziquantel

Flat bodies with muscular suckers/hooks.  

Acquired by eating uncooked plants (water chestnuts/bamboo) or crustaceans. Inflammation, microabscesses of intestines, ulceration, diarrhea, and malabsorption (edema/ascites from protein loss), Vit B12 def, anemia. 

Diagnostics: eggs or adult worms in stool 

Intestinal Flukes (trematoda)

Other name for intestinal flukes

Trematoda

Treatment: Intestinal flukes (trematoda)

Praziquantel

Diagnostic test for esophageal candidiasis

Endoscopy ± biopsy

Candida must be indentified on UA and/or urine culture to diagnose _______

candiduria (funguria

Diagnostic test for pneumocystis jirovecii pneumonia

Bronchoalveolar lavage (BAL) (Almost 100% sensitive and specific for PJP in pts with HIV; negative PCR from BAL rules out disease). 

What condition is diagnosed with a galactomannan assay + CT (halo sign)

Aspergillosis

What are the 2 classic MRI findings of prion disease (CJD)?

1. Cortical ribboning

2. Basal ganglia hyperintensity

What is the gold standard diagnostic for malaria?

Thick and thin Giemsa-stained blood smears

• Thick (detection)

• Thin (identify species and quantifies parasitemia)

What is the classic imaging finding (CT/MRI) of toxoplasmosis?

Multiple ring-enhancing brain lesions

What is the stool microscopy finding differences for Entamoeba histolytica and Giardiasis?

Entamoeba histolytica: trophozoites CONTAINING ingested RBCs

Giardiasis: trophozoities WITHOUT ingested RBCs

In tapeworms, T._____ is implicated in neurocysticercosis which causes intracranial lesions

T.solium

• Found widely in soil and water sources.  

• Infection occurs through inhalation of contaminated aerosols from environmental sources (person-to-person transmission is uncommon).  

• Disease typically develops when host defenses are impaired (e.g., underlying lung disease or advanced HIV/AIDS CD4 <50). 

NTM / MAC

• Caused by Mycobacterium leprae or M. lepromatosis.  

• Primarily affects the skin and peripheral nerves.  

• Transmission is uncommon but occurs via prolonged respiratory exposure, broken skin, or contact with armadillos.  

• Disease exists on a spectrum based on the patient's immune response: ________ leprosy (strong immune response) vs. _______ leprosy (weak immune response with extensive disease). 

Tuberculoid

Lepromatous

Immunocompetent patients mount an immune response where organisms are surrounded in granulomas, which limits multiplication and spread.  

• The infection is contained, not eradicated and the patient cannot transmit organism to others. 

Latent TB

Occurs when the immune response cannot contain the infection.  

• Around 5-15% of patients with latent TB will develop active TB if not given preventative therapy 

• Increased risk of reactivation occurs in patients with Gastrectomy, Silicosis, Diabetes Mellitus, and Impaired immune response. 

Active TB

• opportunistic fungus that is normal flora of mouth, GI tract, vagina.  

• Disease occurs when host defenses are disrupted.  

• Risk Factors: Antibiotic use, Diabetes, Corticosteroids, HIV/AIDS, Immunosuppression (chemotherapy, transplant), Malnutrition, Extremes of age. 

• Esophageal _______ is an AIDS-defining illness. 

• Invasive _______ occurs when candida enters bloodstream and/or deep tissues. 

Candidiasis

• Opportunistic fungal infection found worldwide in the lungs.  

• Serologic data indicates most people have had asymptomatic infections by a young age, suggesting airborne transmission  

• Latent, inactive organisms reside sparsely distributed in alveoli and activate during immunosuppression (like HIV) to cause subacute interstitial pneumonia. 

Pneumocystis jirovecii pneumonia (PJP)

• Infection occurs after inhalation of aerosolized spores.  

• Epidemiology: Endemic in the Mississippi and Ohio River Valleys and Great Lakes region.  

• Assoc. with soil disruption (hunting, camping, excavation).  

• Unlike many other fungi, it often affects immunocompetent individuals. 

Blastomycosis

Caused by Blastomyces dermatitidis (Dimorphic fungus).  

Blastomycosis

Caused by Histoplasma capsulatum (Dimorphic fungus).  

Histoplasmosis

• Found in soil contaminated with bird or bat droppings.  

• Infection occurs after inhalation of spores.  

• Epidemiology: Endemic to Ohio and Mississippi River Valleys (caves, chicken coops, old barns).  

• Progressive disseminated disease poses the Highest Risk to HIV/AIDS, TNF-alpha inhibitors, other immunocompromised. 

Histoplasmosis

Caused by Cryptococcus neoformans (encapsulated yeast). 

Cryptococcosis