Otitis Media causes

• streptococcus pneumoniae
• haemophilus influenza
• moraxella catarrhalis

Streptococcus Pneumniae

• gram + diplococci

Moraxella Catarrhalis

• gram -
• childhood colonization of nasopharynx
• adults direct contact w/oro-nasopharyngeal

Haemophilus Influenza

• small aerobic gram - (coccobacilli)
• type B most virulent (vaccine preventable)
• HEENT: sinus, otitis media, epiglottis
• lung (bronchitis)
• CNS (meningitis)

Otitis Media RX

• Amoxicillin + Clavulanate or Cefuroxime
  • chronic DZ difficult to manage & may not respond to antibiotics

SINUSITIS

• Secondary bacterial infxn
• anaerobes present
• fever, purulent nasal discharge, & sinus tenderness

Moraxella Catarrhalis

• gram - cocci

Sinusitis RX

AMOXICILLIN+CLAVULANATE or cefuroxime

Atypical Pneumonia

• non-productive cough
• no bacteria on smear
• doesn't respond to cell wall antibiotics
• interstitial infiltration

Atypical Pneumonia Pathogens

• mycoplasma pneumoniae
• chlamydophila pneumoniae
• legionella pneumophila

Mycoplasma Pneumoniae

• Atypical pneumonia
• wall less bacteria
• don't grow well
• P2P transmission via droplet or contact

Mycoplasma Pneumoniae symptoms

• CBC: anemia---normal WBC
• clear chest X-ray
• acute onset
• gradual w/dry cough, HA
• fever
• malaise
• sore throat

Mycoplasma Pneumoniae RX

• Azithromycin or Levofloxacin

*cell wall inhibitors like amox or ceftriaxime are ineffective against mycoplasma!!!*

Legionella Pneumophilia

• intracellular bacteria
• environmental source
• NO P2P transmission
• multiply in alveolar macrophages
• cytokine activated limit intracellular growth

Legionella Pneumophila Symptoms

• severe pneumonia in pts >50 yrs
• smoking
• diarrhea
• renal failure
• cell mediated immunity
• POSITIVE antigen assay & culture

Legionella Pneumophila RX

Azithromycin or Levofloxacin

Syphilis RX

• Benzathine PNC G or Doxycycline (if allergic)
• must be + RPR serology before antibiotic given

Plasmodium

• intracellular sporozoan
• species: falciparum (life threatening) & vivax
• mosquito-borne infxn

Malaria Pathogenesis in the LIVER

• reproduction results in 10,000-30,000-fold ampliciation
• tissue schizonts rupture & merozoites are released into blood stream

Malaria Pathogenesis in the BLOODSTREAM

• merozoites infect RBC using Glycophorin A receptor (falciparum)
• Duffy antigen (vivax)
• cytokines (IL-1 & TNF) from macrophages & damage RBC causing higher fever & anemia
• Merozoites cause rupture of RBCs every 48 hrs
  • chill, fever, defervescence 

P. falciparum

• Glycophorin A receptor
• invade RBC of any age
• causes heavy parasitemia

P. vivax

• duffy antigen present
• selectively parasitizes erythroblasts
• Causes younger RBC to expand

Antimalarial Treatment

• For uncomplicated Quinine, Quinidine, or Mefloquine (p.falciparum)
• For complicated use Quinidine w/doxycycline
• plasmodium vivax: quinine or mefloquine w/combo primaquine

Quinine MOA

• appears to interfer w/fxn of plasmodial DNA

Quinine Toxicity

• oral drug may cause hemolysis in pts w/ G6PD deficiency

Quinidine Gluconate MOA

• inhibit heme polymerase activity
• responsible for polymerizing heme into malarial pigment
• may also inhibit aspartic & cysteine proteases that degrade hemoglobin & alkalinize plasmodial food vacuole

*IV in severe malaria

Mefloquine

• Schizonticidal
• against chloroquine-resistant falciparum
• halucinations
• GI upset, circulatory disturbances, rash

Primaquine

• interfere w/pyrimidine synthesis & mitochondrial electron transport chain
• only drug used to treat exoerythrocytic liver forms of vivax

Primaquine toxicity

hemolytic anemia--in pts w/G6-Pd deficiency

Malarone MOA

• atovaquone inhibits 2 different pathways:
  • inhibits pyrimidine biosynthesis @ site different from proguanil
  • inhibits mitochondrial electron transport cytochrome bc1 complex
• proquanil is metabolized-->cyloguanil (dihydrofolate reductase inhibitor)
• atovaquone & proguanil alone are ineffective

Malarone (atovaquone/proguanil) general

• Broad-spread
• antimalarial prophylaxis  in chloroquine-resistant areas
• SAFEST--EXPENSIVE

Artesunate

• derv of artemisinin from sweet wormwood plant
• antimalarial activity dependent on endoperoxide interxn w/intraparasitic heme
• lethal thru accumulation of non-polymerizable redox-active heme adducts
• NOT FDA APPROVED for emergency use

Virulence Factor:  Erythrogenic Toxin

• high fever
• itchy throat
• difficulty swallowing
• petechiae on soft palate
• tonsilar exudate present

Staphylococcus aureus

• diarrhea
• sudden on set of fever
• desquamating rash
• toxic shock syndrome

Staphylococcus Aureus produces...

• Enterotoxin

• TSST-1

Staphylococcus Aureus RX 

Nafcillin & Clindamycin

Virulence Factor: Polysaccharide capsule

• chill & fever
• productive cough--bloody sputum
• high WBC
• pt has community acquired pneumonia

Streptococcus Pneumoniae

•  Levofloxacin--if PNC resistant

Legionella Pneumophila

• watery diarrhea
• plumber
• clear sputum

Reactivation TB

• cough for several weeks
• getting worse w/erythromycin treatment

What vitamin do you give while giving drug regimen for TB?

Vitamin B6

(shiff's base formation)

 Ceftriaxone

• swelling
• vaginal discharge
• septic arthritis

Treponema Pallidum

• syphillis
• painless ulcer

Gram - rapidly growing bacteria

E. Coli

Treatment of E.Coli

Ciprofloxacin

Pseudomonas Aeruginosa

• cystic fibrosis
• pneumonia
• salty skin
• frequent stools
• green sputum

Pseudomonas Aeruginosa RX

Piperacillin + Tobramycin

Bacteroides fragilis

• aerobic & anaerobic
• yields gram - encapsulated

Bacteroides Fragilis RX

Ceftriaxone + Metronidazole

                  (e.coli)       (anti-anaerobe)

Treating pharyngitis (mono) doc must NOT administer...

amoxicillin

target of drug efficacious when given in 48 hrs...

neuraminidase

Reassortment

• genetic changes responsible for devasting spread of infxn