dr. noto id handout (1)

7/23/2019 Dr. Noto ID Handout (1)

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Step 2 Infectious DiseaseFrank P. Noto, MDAssistant ProfessorMount Sinai School of MedicineInternal Medicine Clerkship Site Director

Remember, not freak out over ID.Best of luck!!!!

It is not as bad as you think.RememberThink organ organism antibiotic

Notice that I keep referring to the same themes over and over again:

MSSA: nafcillin, oxacillin, dicloxacillin, cloxaillin OR 1st generation cephalosporins(cefazolin or cephalexin)

MRSA: Vancomycin,daptomycin, if resistant or allergic to vanco (NOT for pneumonia, check CPK) bacteremia, endocarditis, cellulitis

linezolid, (do NOT give SSRIs, watch platelets)

cellulitis, PNAtedizolidtigecycline (use for ESBL E coli that is resistant to imipenem, NOT cover pseudomonas)Quinupristin/dapfopristinCeftaroline (5th generation) community acquired MRSA pneumonia and cellulitistelavancin,

Dalbavancin IV one dose on day one and another does on day 8!!Oritavancin IV one dose!! Skin infections

Mild MRSA skin infections: TMP/SMX, doxy, clindamycin

Group A strep strep throat penicillin, amoxicillin, amp (cephalexin, clindamycin,macrolide for allergy)Serious skin infections due to Group A Strep penicillin AND clindamycin

Enterococcus amp AND gent



Strep viridins penicillin or ceftriaxone plus gent

Gram-Positive Cocci

Penicillin G, VK, ampicillin, amoxicillinEffective against group A streptococcus, most anaerobes (not Bacteroides),

actinomycosis, clostridium (not C. difficile), Listeria, syphilis Not staph: need beta-lactamase inhibiters (sulbactam, clavulinic acid)!Ampicillin is effective against E coli (resistance is rising)Ampicillin and amoxicillin effective for enterococci and Listeria

Gram-Positive CocciSemisynthetic penicillinase-resistant penicillins (oxacillin, cloxacillin, dicloxacillin,nafcillin)

Exclusive Gram-positive coverage, staph and strepDrug of choice for MSSA, more effective than vancomycinIf you see viridans, must be endocarditisBone, heart, joint, skin

*

Gram-Positive CocciCephalosporins Do not cover LAME

ListeriaAtypicalsMRSA - except ceftraolineEnteroccus



1st Gen - cefazolin, cefdroxil, cephalexin,2nd Gen â€“Cephamycins : {cefoxitin, cefotetan} ONLY cephalosporin to coveranaerobes

cefuroxime, cefprozil, cefaclorCoverage same as semisynthetic penicillins, plus some Gram-negative

1st proteus mirabilis, klebsiella, E coli2nd - Providencia, Haemophilus, Klebsiella, Enerobactor, Citrobacter, Morganella,indole-positive-Proteus, Moraxella catarrhalis

Gram-Positive CocciCephalosporins

If treating purely gram positive infection, use 1st generation, 2nd is too broad.Always narrow your coverage!

Gram-Positive Cocci.Clindamycin

Excellent strep, staph and anaerobe coverageUse in penicillin allergyUse for anaerobic infections above diaphragm

Metronidazole

Use for below diaphragm infectionsUse for C. difficile(use Metronidazole for the FIRST recurrence PO vancomycin taperfor 2nd (Fidaxomicin after the 3rd recurrence) PPIs can lead to recurrent cdiffStop PPIs in a patient with C idff

Gram-Positive CocciCephalosporinsAllergic cross-reactivityOnly < 5% riskOk if rash

Never if anaphylaxisIf minor infection - use macrolide or new fluoroqinlones



Serious infections - aztreonam for gram negative, plus vancomycin, linezolid,daptomycin for gram-positive

Daptomycin, linezolid, tigecycline can be used for VRE

Extended-Spectrum Beta-Lactamases (ESBL): E coli and KleseillaAcinetobacter baumanni i

Very resistant gram negatives : First line is imipenem: but now have some resistance

Use Tigecycline for resistance to these organismsTigacyline covers ESBL gram-negative, not pseudomonas.

Ceftolazone/tazobactam ESBL and MDR pseudomonas, complicated UTIs and intra-

abdominal infectionsCeftazidime/avibactam ESBLKPCcarbapenemase (very resistant) GI and serious skin infections

MacrolidesMild gram-positive infectionsAtypical infections

Do not use for serious gram-positive infection

Invasive Aspergillus

In patients with neutropenic fevers after 5 DAYS on antibiotics with new pneumonia

Treatment:

1st line Voriconazole

Caspofungin and Amphotericin B may also be used

Neutropenic FeverANC less than 500Monotherapy with an antibiotic that covers pseudomonas only



If indwelling catheter, add vancomycin for MRSA

Gram-Negative Bacilli

Penicillins (piperacillin, ticarcillin, mezlocillin)

Full range of gram-negative Enterobacteriaceae (E coli, Enterobacter, Klebiella,Citrobacter, Morganella, Proteus, Serratia), plus pseudomonasAdd beta-lactamase inhibitor, tazobactam or clavulanate) to add activity against staph

Gram-Negative BacilliFluoroquinolonesCiprofloxacinGOOD: gram-negative coverage, including Pseudomonas

NO: gram-positive coverage New fluoroquinolones (levofloxacin, gemifloxacin, moxifloxacin)

Very good gram-positive coverage, gram-negative, and atypical (mycoplasma,chlamydia, Legionella)

Gram-Negative Bacilli3rd/4th generation CephalosporinsFull coverage of gram-negative bacilli, such as Enterobacteriaceae (E. coli, Proteusmirabilis, indole-positive Proteus, Klebsiella, Enterobacter, Serratia, Citrobacter),

Neisseria, and H. influenzaeOnly ceftazidime and cefepime (4th gen) will cover pseudomonas

Ceftazidime is not reliable for staph/strepPO: cifixime = gonorrheaPO: cefpodoxime

Gram-Negative BacilliAminoglycosidesGood Gram-negative coverage, including pseudomonasSynergistic with penicillin in treatment of staphUse for endocarditis

Nephrotoxic and ototoxic

AztreonamOnly Gram-negative coverage, use in serious infections with severe penicillin allergyGram-Negative BacilliCarbapenems(imipenem, meropenem, doripenem, ertapenem)Full coverage of Enterobacteriaceae, plus PseudomonasPlus excellent gram-positive and anaerobic coverage

Not MRSA, Enterococcus faecium, or Stenotrophomonas maltophila



Gram-Negative BacilliErtapenemDoes not cover pseudomonas

Approved for intra-abdominal and soft tissue infectionsLower seizure threshold, especially imipenem

Gram-Negative BacilliDoxycyclineEarly lyme - rash, joint problems, facial palsyRikettsieaChlamydiaEhrlichiosis

Trimethoprim-sulfamethoxazolePCPUncomplicated cystitis

Meningitis

Streptococcus pneumoniae

Neisseria meningitidisListeria monocytogenes: HIV, steroids, lymphoma, leukemia, chemo, neonates andelderly (> 50)CryptococcusRocky Mountain Spotted fever mid-AtlanticTb, Lyme disease, syphilisViruses: entero, HIV, HSV, West Nile, St. Louis

Meningitis:

Fever, photophobia, headache, nuchal rigidity, N/VAMS, seizures8th cranial nervePetechial rash: Neisseria

CT head if: focal motor deficits, seizures, papilledema, severe AMS,immunocompromised (HIV, transplant, immunosuppressive meds)



DO NOT delay treatment: start empiric antibiotics

Meningitis

Normal cell count is < 5Bacterial: cell count in thousands all neutrophils

High protein and low glucoseGram stain is positive only 50 to 70%Cell count of several dozen to hundreds with lymphocytes: viral, Lyme, Tb, syphilis,fungal, Rikettsia

Meningitis

Treatment

Ceftriaxone and vancomycinAmpicillin if over 50 or 3 months old, HIV, steroids, hematologic malignancies,

pregnancy

MeningitisCryptococcus: amphotericin B, followed by fluconazole in HIV for life or until increasein CD4 count to > 100 for 3 to 6 months on HAARTCryptococcus neoformans: India ink and crypto antigen titer

Tb, treat for 9 -12 months

MeningitisSteroids in Tb and streptococcus meningitis

Dexamethasone 15-20 minutes before or with antibioticsNeurocysticercosis

Ingestion of Taenia solium, also called the pork tapewormChina, Southeast Asia, India, sub-Saharan Africa, and Latin AmericaPrevalence of cysticercosis in Mexico is between 3.1 and 3.9 percentCT scan: calcified and uncalcified cysts, as well as distinguishing active and inactivecysts. Cystic lesions can show ring enhancing and focal enhancing lesions.Albendazole

Brain Abscess

Spread from mastoiditis, dental infections, sinusitis, otitis media, bloodstream

Streptococcus: 60 to 70% (viridans streptococci, Streptococcus milleri, microaerophilicstreptococci)Bacteriodes fragilis: 20 to 30% (high resistance to clindamycin)Enterobacteriaceae: 25 to 35 %,



Staphylococcus 10%

Headache and fever, focal deficits in 60 %, seizuresCT scan or MRIAspiration or excision in essential for gram stain and culture

Brain AbscessIn HIV, 90% are toxoplamosis vs. lymphomaTreat with pyrimethamine and sulfadiazine for 10 to 14 days

Always need surgical drainage and medical therapy

Combination with penicillin or a third generation cephalosporin and metronidazoleThird generation cephalosporin and Metronidazole (NOT clindamycin) andvancomycin for sinusitis

Penetrating trauma or after neurosurgeryVancomycin and a third generation cephalosporin

Encephalitis

Viral: HSV-1, varicella-zoster, CMV, enteroviruses, Eastern and Western equine, St.Louis, West Nile

Headache and fever with AMSLethargy or coma, focal deficits, seizures. Need LP: PCR for HSV has 98 % sensitivity and 95 % specificityCT may show temporal lobe involvement.IV acyclovir

Sinusitis

Maxillary is most common

Facial pain, headache postnasal drainage, purulent drainage, fever, tooth pain

Imaging not usually neededCT scan if no response to therapy

90% to 98% are caused by viruses NSAIDs and decongestants



Antibiotics if:Symptoms last for at least 10 daysIf symptoms are severe: fever over 102Â° and facial pain for three to four successivedaysIf symptoms worsen, usually after a viral upper respiratory infection of five

SinusitisHaemophilus influenzae and Moraxella catarrhalisAmoxicillin-clavulanateDoxycycline or new fluoroquinolone

Pharyngitis

Strep pyogenes, group A beta-hemolytic strep 15 to 20%Majority are viral

Rapid strep test is 60 to 100% sensitive, but 95% specificIf negative, should confirm with culture

Penicillin, ampicillin or amoxicillinMacrolides, 1st generation cephalosporins, clindamycin

Influenza

Fever, myalgias, headache, fatigue, coryza, nonproductive cough, sore throatRapid antigen detection, swab of nasopharyngeal secretionsSymptomatic therapy

Neuraminidase inhibitors: oseltamivir and zanamivir (48 hours)Amantadine and rimantadine effective against Influenza A NOT used much

Vaccinate Everyone!

Bronchitis

Acute bronchitis NO antbiotics!!!!

Acute inflammation of tacheobroncheal tubeMostly viral, M. pneumonia, C. pneumoniae



Chronic bronchitis COPD exacerbation:

Streptococcus pneumonia, H. influenzae, MoraxellaCough with sputum

May have low grade feverDiscolored suggest bacterial etiologyBronchitisCough with sputum, no fever and a normal CXR

Acute exacerbations of chronic bronchitis can be treated with amoxicillin, doxycycline,TMP/SMZ

Repeat infections should get amoxicillin/clavulinate, macrolide, 2nd or 3rd generationcephalosporin, new fluoroquinolones

Lung Abscess

90% have anaerobes involvedPeptostreptococus, Prevotella, Fusobacterium are most common85 to 90% have periodontal disease or aspiration

Fever, cough, sputum, chest painPutrid, foul-smelling sputum and a more chronic coughSeveral weeks of weight loss, anemia, fatigueLung AbscessCXR will show thick-wall cavity

Need aspiration of abscess for diagnosisClindamycin is first linePenicillinMost respond to antibiotics and do not need drainage

Pneumonia

Sixth leading cause of deathRisk factors: DM, ETOH, smoking, malnutrition, immunosuppressionMost common: Community-acquired pneumoniaStrep pneumonia (15-35%)Haemophilus (2-10%)Atypical Legionella (15%)



Mycoplasma (10%)Chlamydia (5-10%)Viral

Pneumonia

Haemophilus influenzae - smokers, COPDMycoplasma -healthyLegionella - air conditioningPneumocystis jiroveci - HIVCoxiella burnetti (Q-fever) - exposure to animalsKlebsiella - alcoholicsStaphylococcus aureus - post influenzaCoccidioidomycosis - southwest (Arizona)

Pneumonia

Chlamydia psittaci - birdsHistoplasma capsulatum - bird droppings, spelunking, batsBordetella pertussis - cough with whoop and post-tussive vomitingFrancisella tularensis - hunters, rabbitsAvian infuenza - Southeast AsiaBacllus anthracis, Yersina pestis Francisella tularensis - bioterrorismPneumoniaCough, fever, sputum production, dyspneaKlebsiella - current jelly

Rales, rhonchi, dullness to percussion, egophonyRR, hypoxia leads to hyperventilationCXR-lobar PNA S. pneumoniaInterstitial infiltrates - PCP, viral, atypicalSputum for Gram stain and culture

PneumoniaTreatmentSeverity:Hypoxia, PO2 < 60 (< 94%),

RR > 30Confusion, uremia, hypotensionHigh fever, leukopenia, tachycardia, hyponatremia

Outpatient â†’

empiric therapyMacrolide or new fluoroquinolone



PneumoniaTreatment:

Inpatient New fluorquinolones, or2nd or 3rd generation cephalosporins (ceftriaxone, cefuroxime) with macrolide or doxy,orBeta-lactam/beta-lactamase combination, with macrolide or doxy

Community-Acquired MRSA pneumonia

Think about it and cover it when you have:

Necrotizing or cavitary pneumoniaIV drug usersSevere pneumonia requiring admission to the ICU

EmpyemaGram-positive cocci in clusters on sputum Gram stainRecent antimicrobial therapyRecent influenza-like illness (they love this on USMLE, almost as much I love beer!!)

Community-Acquired MRSA pneumonia use ONE of the following :

Ceftriaxone and Vancomycin and azithromycin



OR Linezolid and ceftriaxone and azithromycinOR Clindamycin and ceftriaxone and azithromycin

OR Ceftaroline (the one and only cephalosporin to cover MRSA) and azithromycin

Hospital (ventilator) -Acquired Pneumonia

After 48-72 hours in the hospitalAfter 5 days, you must cover MDR organismsPseudomonas, Klebsiella, E coliMRSA

MUST give 2 for pseudomonas and one for MRSA 3 antibiotics total!!

Ceftazidime OR

Cefepime ORPipercillin/tazobactam ORTicarcillin/clavulinate ORImipenem, meropenem, doripenem ORAztreonamthe answer when serious gram negative infection with anaphylacticreaction to penicillin

PLUS

Cipro (or levofloxacin)

OrGentamycin (or any aminoglycoside) not in renal failure

PLUS

Vancomycin ORLinezolid

Pneumonia

Pneumonia Vaccine> 65, serious underlying lung, cardiac, liver, renal disease, steroids, HIV,splenectomized, diabetics, hematological malignancies.Re-dose in 5 years if severely immunocompromised

TuberculosisMycobacterium tuberculosis



Tuberculosis

Active: Productive cough, fever, weight loss, night sweatsLymph node, meningeal, GI, GU - extrapulmonary sitesCXR - apical infiltrates or cavities, effusions, calcified nodules

Sputum staining for acid-fast bacilli (need 3 negative to rule out Tb), culture takes 4-6weeksTuberculosisTreatmentIsoniazid, rifampin, pyrazinamide, ethambutol for 2 months or when sensitivity is backContinue INH and rifampin for 4 more months

TuberculosisLatent Tb positive PPD or positive quantiferon gold or the interferon-gamma releaseassays (IGRAs) (check this instead of PPD in patients who received the BCG)

With a negative chest X-ray

> 5 mm: close contacts, HIV, abnormal CXR consistent with old Tb, steroid use or

organ transplant recipients

> 10 mm: healthcare workers, prisoners, NH residents, immigrants (5 years), homeless,immunocopromised (hematologic malignancies, DM, dialysis, IV drug users)> 15 mm: low riskPositive PPD and negative CXR: 9 months of INHIf positive CXR, collect sputum for AFB

*Viral HepatitisHepatitis A and EOral/fecal routeIncubation 2-6 weeks, Acute infection for days to weeks

Hepatitis B, C, DParental route

B and C can be chronic

Viral HepatitisPresentationAcute - jaundice, dark urine, light stools, fatigue, malaise, tender enlarged liver



Hep C can cause cryoglobulinemiaHep B associated with PANHep D can only be co-infected with B

Viral Hepatitis

DiagnosisALT higher than ASTHigh bilirubinAlkaline phosphatase and GGT less elevatedHigh PT in severe diseaseCheck pcr-RNA viral load for hep C to access activity

Hepatitis BSurface Ag = infected

Surface Ag + IgM Core Ab = acute infectionSurface Ag + IgG Core Ab= chronic infectionCore Ab:IgM = acute infectionIgG = 1) chronic infection (if Hep Bs Ag), or2) recovery (if Hep Bs Ab)

Hepatitis BSurface Ab = vaccinated

Resolution of infection = Hep Bs Ab, IgG Hep Bc Ab (exposed, recovered, and immune- 95%)Window period = Hep Bc IgG antibody and Hep Be antibody (2-6 weeks between theloss of surface antigen and development of surface antibody)

Hep Be Ag = high replication rate and highly infectious

Viral HepatitisTreatmentAcute hepatitis - supportive care.Chronic hep B – Tenofovir (can cause fanconi syndrome) and Entecavir preferred.interferon, adofovir, lamivudine, telbivudin (these agents have more resistance)Cirrhosis - liver transplant

Needle stick hep B - hep B Immunoglobulin and vaccine if not immune



Chronic Hepatitis C

• Antibody to hepatitis C with elevated viral load for hepatitis

C RNA by PCR

•

Genotype 1 and 4:• Ledipasvir-sofosbuvir or sofobuvir-simeprevir+/- ribavirin • Genotype 2 and 3: • sofosbuvir and ribavirin

Sexually Transmitted Infections (STIs)

UrethritisPurulent discharge, dysuria, urgency, frequency

Neisseria gonorrhea NongonococcalChlamydia trahcomatis (50%)Ureaplasma urealyticum (20%)Mycoplasma hominis (5%)Trichomonas (1%)HSV (rare)

**

STIs: Gonorrhea

Disseminated Gonorrhea

Classic triad of dermatitis, migratory polyarthritis, and tenosynovitis

Skin findings

Small macules or hemorrhagic pustules on an erythematous base located on palms

and soles or on the trunk AND elsewhere on the extremities



STIs: Gonorrhea

DiagnosisBlood smear shows gram-negative, coffee bean-shaped intracellular diplococciCulture for gonorrhea

Serology for Chlamydia by swabbing urethra, orLigase chain reaction test of urine

STIs: GonorrheaTreatmentOne dose of ceftriaxone IM or cefixime PO and azithromycin POAlternative is doxycycline for 7 days

(NOT FQ)

Fever, discharge, leukocytosis, lower abd painCERVICAL MOTION TENDERNESS, adnexal tenderness or uterine tenderness!!

DiagnosisCulture on Thayer-Martin for gonococcus and Gram stain of discharge

STIs: PIDTreatment

Single dose IM ceftriaxone and oral doxycycline for 2 weeksOROfloxacin and metronidazole (both oral) for 2 weeks

Hospitalize if high WBC or feverTreat with doxycycline and cefoxitin or cefotetan

Syphillus

Spirochetes are Gram-negative bacteria that are long, thin, helical and motile via axialfilaments (a form of flagella)Primary infectionChancre in 3rd week and disappears in 10-90 days, painless lymphadenopathySecondary infectionCutaneous rash during 6-12 weeks - symmetric, more on flexor and volar surfaces,



condylomata lata, papaules at mucocutaneous junctions

STIs: Syphilis (Treponema Pallidum)STIs: SyphilisLatent

Asymptomatic, 1/3 develop tertiaryTertiary or late3-20 years later - gumma in any tissue

Neurological and CV manifestations (aortitis)

STIs: Syphilis

Other long-term sequelaeArgyll Robertson pupil

Small, irregular, reacts to accommodation, but not to lightTabes dorsalis3 to 20 years after infectionPain, ataxia, sensory changes, loss of tendon reflexSTIs: SyphilisDiagnosisScreening = VDRL, RPRMore specificFTA-ABS (Fluorescent Treponemal Antibody absorption)

MHA-TPDarkfield of chancre NeurosyphilisFTA of CSF is more sensitive than a VDRL

TreatmentPrimary/secondary/early latent (less than one year)Penicillin G, IM times one

Tertiary (gummas, CV manifestations) /

Late latent (more than one year, VDRL or RPR titers elevated >1:8 without symptoms)Penicillin G, IM once a week for 3 weeks

STIs: SyphilisTreatment (contâ€™d)

Neurosyphilis (includes ocular syphilis)Penicillin IV for 10 to 14 days



Doxycycline for penicillin G-allergy in primary and secondary

Pregnant or neurosyphilis must be desensitized

STIsHSVVesicles become eroded and painfulItching and soreness precedePCR (NOT tzanck culture)Acyclovir, valacyclovir, famciclovir

UTIsCystitisDysuria, frequency, urgency, suprapubic pain

Urinalysis for WBC, RBC, nitrites, Gram-neg infxnUrine culture with >100,000 is confirmation, but not necessaryTrimethoprim/sulfamethoxazole, nitrofurantoin, or quinolone for 3 days7 days if DM or complicated-stones, strictures, obstruction, pregnant, men

No quinolones in pregancy

UTIsPyelonephritisObstruction due to tumor, stricture, calculi, PBH, neurogenic bladder, or vesicoureteral

refluxE. coli most common. Also Proteus, Klebsiella, Enterococcus.Candida in immunocompromised or with Foley cathSymptoms: Fever, chills, flank pain, n/v, CVA tenderness, urinary complaintsDiagnosis: urinalysis and urine culturesAlways get cultures before starting antibiotics!

UTIsTreatment

3rd generation cephalosporin, fluoroquinolone, amp and gent10-14 days of antibioticsDo not use TMP/SMZ for empiric therapy due to up to 20% resistance



Skin Infections

CellulitisInfection involving subcutanous tissueLocalized pain, erythema, edema, warmthMost commonly: Staph and group A Strep (GAS), Strep pyogenesDicloxacillin or cephalexin

If life-threatening diabetic foot infection: must cover gram negatives and anaerobes:Use imipenem and vanco!!

If CA-MRSA think about when you see: purulent drainage/abscess, MSM, prisoners, athletes, American IndiansTreatment:

bactrim, clindamycin, vancomycin, linezolid, ceftaroline, or doxycycline

Skin InfectionsCat bites and dog bites

Pasteurella multocidaResistant to dicloxacillin and nafcillin

Dog and human bitesFusobacterium, Bacteroides, Eikenella corrodensDOGS capnocytaphia (life threatening in aspenic patients)

Augmentin (amoxicillin/clavulanate)

Oral clindamycin + fluoroquinoloneOral clindamycin + tetracyclineOral clindamycin + trimethoprim/sulfamethoxazole (pediatric)



Skin InfectionsNecrotizing Fasciitis

Immediate Surgical debridement is most important!!Group A strepPenicillin G (or 1st or 2nd generation cephalosporin) plus clindamycinMixed aerobes and anaerobes

Vancomycin PLUS

1) piperacillin-tazobactam or

2) cefepime and metronidazole or

3) meropenem or imipenem

PLUS clindamycin (to stop group A strep toxin production)

Skin Infections

Gas GangreneFever, severe pain and swelling, crepitusDeep cuts and black tar heroineX-ray â†’ feathery gas pattern Clostridium perfringensPenicillin plus clindamycinSurgical debridement and hyperbaric oxygen

Vibrio vulnificus

Fisherman, Gulf of Mexico

Cirrhosis (HEMOCHROMOTOSIS) and poorly controlled DM



Dark bullous lesions

Wound infections leading to septicemia

3rd generation cephalosporin (ceftazidime, cefotaxine, ceftriaxone)AND

doxycycline or ciprofloxacinLIFE THREATENING!!!!

Bone and Skin Infections

OsteomyelitisPresentationPain, erythema, edema, tenderness

X-ray (1st test)Periosteal elevation, 50-75% of bone loss before abnormal, takes 2 weeksESR

Normal value strongly against OM, used to follow up treatment

Bone and Skin InfectionsOsteomyelitisDiagnosisBone biopsy and culture is the best test (not swabs of sinus tract or ulcer)

Never culture the draining sinus tract!!!!

CT, indium, gallium Not as sensitive or specificCT scan MRI

Bone scan is crapy!!

MRI allows for better differentiation between bone and soft tissueAlways get MRI if you canCannot get MRI if patient has metal get CT scan

Bone and Skin Infections



OsteomyelitisTreatmentWound drainage and debridementIV Antibiotics for 6 weeks, get sensitivitiesChronic OM â†’ treat for 12 weeks

DM - 30% gram negative â†’ cipro (only oral abx can be used for OM)

Bone and Skin InfectionsOsteomyelitisTreatmentEmpiric therapy (low yield)

1) piperacillin/tazobactam, ampicillin/sulbactam, ticarcillin/clavulanic acid2) Third or fourth generation cephalosporin with metronidazole3) Clindamycin plus cipro or levofloxacin

If concern or proof of MRSAVancomycin, linezolid or daptomycin

Bone and Skin infections

Septic Arthritis NongonococcalGram positive (>85%)S. aureus (60%)

Streptococcus (15%)Pneumococcus (5%)Gram negative (10-15%)

Septic Arthritis

Monoarticular, swollen, hot, tender, erythematous, decreased ROMJoint aspirate

Cell count >50,000-PMN, low glucose

2000-20,000 = inflammatoryCulture positive in 90-95%

Gonococcal - Polyarticular in 50%Tenosynovitis, effusions less commonMigratory, petechiae



Septic Arthritis

Diagnosis

Culture cervix, rectum, urethra, pharynxOnly 50% positive cultures

TherapyJoint aspiration and antibiotics

EmpiricVANCOMYCIN and CEFTRIAXONE!!!!

Or vancomycin and anything that covers gram negatives like gentamycin

Endocarditis

Infective endocarditis

AcuteS. aureus, normal valvesLarge bulky vegetationsRapid onset with fever

Abscess and rapid valve destructionEndocarditisEmbolic, especially lung

SubacuteViridans most commonAbnormal valvesRisk factors:



Endocarditis Native valves:Streptococcus viridans 50-60 %

Endocarditis: Treatment

ID organismEmpiric: Vancomycin (or daptomycin ) and gentamicin

Strep viridans: Penicillin 4 weeks OR penicillin or ceftriaxone PLUS gentamicin

for 2 weeks

Vancomycin or ceftriaxone for pen-allergic

MSSA: Nafcillin PLUS (5 days of) gentamicin for 4-6 weeks

Cefazolin or vancomycin PLUS gentamicin for pen-allergic

MRSA: Vancomycin for 4-6 weeks

Enterococcal

Penicillin or ampicillin AND gentamicin for 4-6 weeksVancomycin AND genatmicin for 4-6 weeks for pen-allergic

Endocarditis: TreatmentSurgery (high yield)

CHF, recurrent septic emboli, regurgitation that affects hemodynamic functions,

vegetation larger that 10 mm

Fungal, extravalvular infection (AVB, purulent pericarditis), prosthetic valve

obstruction, recurrent infection or persistent bacteremia, abscess or fistula

EndocarditisProphylactics high yield

-prosthetic valves, history of IE, most congenital malformations, especially cyanoticlesions if not repaired.-dental procedures

NO prophylaxis:-Urinary, GI,



-corrected pulmonary shunts, rheumatic valves, HOCM,-MVP with regurgitation, repaired intra-cardiac defectsEndocarditisAmoxicillin, if allergic, clindamycin, macrolide or cephalexin

Acute PericarditisChest pain is sharp. Improved with sitting forwardPericardial friction rub. Low grade feverTamponode: pulsus paradoxus: 10 mm Hg drop in BP with inspiration. Distended neckveins, tachycardia, hypotensionEKG: diffuse ST elevationsPR depressions

Echo to look for effusions

Acute Pericarditis NSIADSColchicine for recurrencePericardiocentesis and pericardial window if large effusions causing tamponade

Lyme Disease

Borrelia budorferiIxodes scapularis3 -30 days: erythema migrans, fever, chills, myalgias7th cranial nerve, facial paralysis (Bellâ€™s palsy) Meningitis, encephalitis, memory lossAV heart block, myocarditis, pericarditisJoint involvement months to years later- 60 %, migratory polyarthritis

Lyme disease

Serologic testing-ELISA with western blot. May be negative early in disease and cannot distinguish between old and new disease.Minor disease treat with doxycyline or amoxicillinCardiac (high degree AVB and PR > 3 s) and serious neurological manifestations

(meningitis) treat with IV ceftriaxone, cefotaxime,



Ehrlichiosis

.Vector:American dog tickDeer tickLone Star tick

EhrlichiosisFevers (90 %)Headaches (>85%)

Rigors (60%) Nausea (40%) Vomiting (40%), Anorexia (40%)Fatigue.A rash is uncommon

lymphopenia, and/or thrombocytopenia

Abnormal liver enzymes are found in 86% of patients.

EhrlichiosisDoxycycline

Babesiosis

Babesia microti, a parasite of small rodents

Northeastern United StatesBabesia divergensIxodes scapularis is the carrier

Fever, fatigue, headache, arthralgia, and myalgia Nausea, vomiting

Abdominal painAnemia

Thrombocytopenia, splenomegaly

BabesiosisDiagnosisParasite on Giemsa-stained blood smearsAn indirect immunofluorescent antibody test for B microti antibody is detectable within



2â€“4 weeks after the onset of symptoms and persists for months Diagnosis can also be made by polymerase chain reaction

BabesiosisTreatmentMild illness: oral atovaquone plus azithromycin for 7â€“10 days Clindamycin plus quinine is the second choice

HIV

HIV infects subset of T lymphocytes called CD4 cells, causing a decrease in the CD4

count, increasing the risk for opportunistic infections and certain malignancies.MSM, IV drug users, heterosexual intercourse10 year lag between contracting HIV and the first symptomsCD4 count drops 50-100 uL/year

Normal CD4 count is 700/mm3

HIV: Opportunistic Infections

Pneumocystis jiovecii

Trimethoprim-sulfamethoxazole (first line)Dapsone and trimethoprim

Primaquine and clindamycin

Atovaquone

Pentamidine IV

Steroids if PaO2 < 70 or A-a gradient of > 35 mm Hg


Pneumocystis jiovecii

Prophylaxis (< 200)TMP/SMZ PO

Dapsone

Atovaquone

Aerosolized pentamadineDiscontinue if CD4 over 200 for 6 months




Cytomegalovirus (HHV-5) (CD4 < 50)Retinitis: blurry vision, double vision, any disturbancesColitis: diarrheaEsophagitis: odynophagia, fever, CP, ulcersEncephalitis: AMS, cranial nerve defects

Fundoscopy: retinitis: yellowish-whitish granules with perivascular hemorrhages andexudatesBiopsy-intra-nuclear inclusion bodies (owlâ€™s eyes) HIV: Opportunistic InfectionsCytomegalovirus (HHV-5) (CD4 < 50)Valganciclovir oral and intravitreal ganciclovirIV ganciclovir CNS infectionsCidofovirFoscarnet

HIV: Opportunistic InfectionsCytomegalovirus (HHV-5) (CD4 < 50)Ganciclovir - neutropeniaCidofovir - renal toxicityFoscarnet - renal failure


Mycobacterium avium complex (CD4 < 50)Inhaled or ingestedFevers, night sweats, wasting, anemia, diarrheaBlood culturesBone marrow, liver, other body tissue culturesTherapy: clarithromycin and ethambutol +/- rifabutinProphylaxis (CD4< 50): azithromycin PO weekly or clarithromycin 2 X a dayHIV: Opportunistic InfectionsToxoplasmosis (CD4 < 100)Headache, confusion, seizures, focal deficits

CT or MRI show ring enhancing lesion with edema and mass effectDiagnosis is the shrinkage with treatment!Toxo serology and CSF polymerase chain reaction to T. gondii, IgG will be positiveBrain biopsy if no shrinkage in 2 weeks

HIV: Opportunistic InfectionsToxoplasmosis (CD4 < 100)Pyrimethamine and sulfadiazine



Clindamycin and Pyrimethamine in sulfa allergiesGive with leucoveorin to prevent bone marrow suppressionProphylaxis: TMP/SMZ or Dapsone/ Pyrimethamine


Crypotococcosis ( CD4 < 100)Meningitis: fever, headache, malaiseLP with India ink and cryptococcus antigenSerum cryptococcus antigenHigh titer and high opening pressure: worse prognosisAmphotericin B IV and flucytosine for 10â€“14 days, then fluconazole PO formaintenance until CD4 is above 100 for 3 to 6 months

HIV: VaccinesPneumococcus, influenza and hepatitis BIf CD4 is over 200 â†’ give varicella vaccine

HIV: CD4 cell count700 or above: normal200 to 500: oral thrush, Kaposi, Tb, Zoster, lymphoma100 to 200: PCP, dementia, progressive multifocal leukoencephalopathy, histoplasmosis

and coccidiomycosis< 100: toxoplasmosis, Cryptopoccus, cryptosporidiosis, disseminated herpes simplex< 50: CMV, MAC, CNS lymphoma

HIV: Viral loadBest method to monitor adequate response the therapy on HAART: goal is undetectableviremiaHigh viral load indicates that the CD4 count will drop more rapidlyViral sensitivity testing should be done if patient is failing HAART or pregnant patient

who has not been fully suppressed on meds

HIV: Antiretroviral Therapy Nucleoside Reverse Transcriptase InhibitorsZidovudine (AZT) - leukopenia, anemia, GIDidanosine DDI - pancreatitis, peripheral neuropathy, lactic acidosisStavudine (D4T) - periperhal neuropathyLamivudine



EmtricitabineTenofovir - nucleotide analog

HIV: Antiretroviral Therapy Nucleoside Reverse Transcriptase Inhibitors

Abacavir (NOT A PI, A is for AIDS) - hypersensitivity-rash, fever, N/V, sob, muscleachesZalcitabine - pancreatitis, peripheral neuropathy, lactic acidosis

HIV: Antiretroviral Therapy the A is for AIDS before the vir!!!Protease InhibitorsHyperlipidemia, hyperglycemia, elevated LFTâ€™s Lipoatrophy, redistribution to neck and abdomen

Nelfinavir - GIIndi navir - nephrolithiasis, hyperbilirubinemia

Rito navir â€“ GI Darunavir navir

Nelfi navir Fosamprenavir

HIV: Antiretroviral TherapyProtease InhibitorsSaqui navir - GI

AmprenavirLopi navir /Ritonavir - diarrheaAtaza navir - diarrhea, hyperbilirubinemiaTipranavir

HIV: HAART

Only statins safe with HAART areRouvastatinPravastatin

HIV: Antiretroviral Therapy Non-Nucleoside Reverse Transcriptase InhibitorsEfavirenz - neurological, somnolence, confusion, psychiatric

Nevirapine - rash, hepatotoxicity



Delavirdine - rashRilpivirine

HIV: Antiretroviral TherapyWhen to start?

CD4 < 500What to start?2 nucleosides and one protease inhibitor or2 nucleosides with efavirenz or2 nucleosides with 2 protease inhibitorsEmtricitabine, Tenofovir, and Efavirenz

HIV: Antiretroviral TherapyGuidelines

2 NRTIs with NNRTI or PIBoosted PI: PI with ritonavir: alone: modest efficacy and significant drug interactionsLow dose in combination with other PIs gives the other PI a â€� boostedâ€� PI: lastlonger and increases the chances of success.Never pick Ritonavir as the answer if it is the only PI

Raltegravir A for AIDS before vir

Integrase inhibitorUsed for resistance to reverse transcriptase inhibitors or protease inhibitorsHIV: Antiretroviral TherapyGoal of therapyDrop of at least 50% of viral load in the first month!

HIV: Antiretroviral TherapyPregnant patients:

Start triple therapy IMEDDIATLEY regardless of CD4 count25â€“30% will be positive without treatment Women with low CD4 and high viral load should get triple therapyC-section if not controlled (viral load over 1000)Start therapy as soon as you know the patient is pregnantEfavirenz is teratogenic

HIV



Post exposure prophylaxisAZT, lamivudine, nelfinavir or another 3 drug regiment for 4 weeks

Neutropenic fever = pseudomonas!!!!!!

Psuedomonas:Cover in 1)neutropenic fever2)nosocomial and ventilator associated pneumonia3)burns4)cystic fibrosis5)ONLY serious diabetic foot infections or when the patient is soaking the foot in a hottube!!

Not need to cover in mild diabetic foot infections!!

Ceftazidime 3rd generation

Cefepime 4th generationPipercillin/tazobactamTicarcillin/clavulinateImipenem, meropenem, doripenemAztreonamthe answer when serious gram negative infection with anaphylacticreaction to penicillin

Cipro and gentamycin DO cover pseudomonas but we prefer a Beta-lactam if we do not

have sensitive’s (Beta-lactams are Best )

Ceftriaxone is a 3rd generation cephalosporin (NOT COVER pseudomonas!!) it is theanswer for:

1) Community acquired pneumonia that needs be admitted WITH a macrolide ordoxycycline

2) Meningitis WITH vancomycin and maybe add ampicillin for listeria

3) Pyelonephritis4) Septic arthritis WITH vancomycin5) Lyme disease with AV block or meningitis6) Spontaneous bacterial peritoneal treatment or prophylaxis in a cirrhotic with

bleeding varices7) Gonorrhea (with azithro or doxy for chlamydia )

8) Vibrio vulnificus with doxy or cipro



9) GI infections with metro

Intraadominal infections:

1)ascending cholantitis2)diverticlulitis3)cholecystitis

Must cover gram negative and anaerobes (especially B fragilis)Can use ANY of the following:

1) Cipro and metronidazole2) Ceftriaxone or cefotaxime and metronidazole (avoid ceftriaxone in biliary disease causes biliary sludge)

3) Amp/sulbactam

4) Ertepenem5) Pipercillin/tazobactam6) Moxifloxicin

B fragilis is resistant to clindamycin !!

Spontaneous bacterial peritonitis cover E coli and pneumococcus cefotaxime or

ceftriaxoneGive prophylaxis with norfloxin, cipro or TMP/SMX for life after one episode

Lower yield :

Q-feverCoxiella burnettiInhalation of placenta of cattle, sheep and goatsAtypical pneumonia, hepatitis, endocarditis, hepatomegalyDoxycycline

Rocky Mountain Spotted FeverRickettsia rickettsi



Wood tick in mid-Atlantic coast, Midwest3-5 days after campingTriad1) Abrupt onset of fever, 2) headache and 3) rash (erythematous maculopapules) onwrists and ankles (palms and soles)

Confusion, lethargy, irritability, stiff neckGI symptomsDx: Biopsy of lesion / Rx: Doxycycline

TetanusComplication of wounds caused by Clostridium tetani, a Gram-positive rodTonic spasms of muscles, respiratory arrest, dysphagia, irritability, stiff neck andextremities

Lock jawHigh mortalityTetanus toxoidWound care, debridementAntitoxin tetanus immunoglobulinRx: Penicillin 10-14 days

BlastomycosisRotting organic material

Southeast and central USInhalation of decaying woodImmunocompetentPulmonary with fever, cough weight lossDisseminates anywhere-skin most common

BlastomycosisIsolation of fungus in sputum, pus, or biopsyAmphotericin for severe disease

Itraconazole or ketoconazole for mild disease for 6-12 months

Toxic Shock syndromeStaph aureus (toxin TSST-1)Tampons, sponges, surgical woundsHypotension, fever, mucosal changes, desquamative rash on hands and feet.GI renal hepatic symptoms

dr. noto id handout (1)

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