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Rapidly Fatal Infections. Eric D. Katz, MD, FACEP Program Director Vice-Chair for Education. You’ve seen this patient…. 40 y.o. male Temp 39.0, BP 60/palp, HR 140 (ST) Multilobar pneumonia How do you treat him? Did I mention his immunocompromise? What if he has MRSA risks?
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Rapidly Fatal Infections Eric D. Katz, MD, FACEP Program Director Vice-Chair for Education
You’ve seen this patient… • 40 y.o. male • Temp 39.0, BP 60/palp, HR 140 (ST) • Multilobar pneumonia How do you treat him? Did I mention his immunocompromise? What if he has MRSA risks? This could easily be rapidly fatal
You might have seen this patient • 40 y.o. male • Temp 39.0, BP 60/palp, HR 140 (ST) • Recent travel to Mexico • CXR shows diffuse interstitial process How do you treat him? Is this rapidly fatal?
By the end of this lecture you will: • Understand how our diagnoses of infectious disease may advance over the next few years • Understand 3 rapidly fatal infections • Understand clinically useful tips to identify rapidly fatal infections from non-threatening diseases
The future of managing infectious diseases Changing our diagnostic abilities
Short incubation culture systems • Now on the market • Faster detection of infection and rapid susceptibility testing • Sensitivity variable • Poor detection of resistance
Direct Antigen Testing • Available for legionella, hemophilus, strep and mycoplasma • Sensitivity and specificity are very variable • Use in clinical practice not defined • At best level 2C indication
Proteonomics Assessment of upregulation and downregulation of several thousand proteins in different disease states. Role in clinical care not established.
A Rapidly Fatal Infection First Case 52 yo DM male had minimal trauma to chest 4 days ago. Then developed spreading redness on chest wall, which has progressed to a painless lesion.
Necrotizing Fasciitis • Usually in middle-aged patients • Young patients often infected after slight trauma • Rising incidence likely from more immunocompromised patients and injection drug users • DM, Cancer, EtOH, PVD, transplant, HIV, neutropenia
Necrotizing Fasciitis • Begins as cellulitis, then progresses to involve fat, fascia and muscle • Bugs: Often polymicrobial. Very often with synergistic organisms Up to 70-80% Mortality rate
Necrotizing Fasciitis - Detection • Early • May show mild superficial skin changes – sharp demarcation of erythema and very rapid spread • POOP • Late • Pain progresses to anesthesia • Extensive edema • Crepitus • Cyanosis
Fournier’s Gangrene • A variant of necrotizing fasciitis involving the perineum, perianal or genital areas • Ofter preceded by local infection, surgery, trauma or foreign body. • Differs from other NF • Older onset • Delay to seeking treatment (5 days)
Necrotizing Fasciitis: Diagnostics • Find the gas! • XR: good PPV, poor NPV • Possible role for ultrasound • On CT, absence of tissue enhancement after IV contrast suggests necrosis • CT may help surgeons with planning
Necrotizing Fasciitis - Treatment • Antibiotics • Coverage for GPC, GNR and clostridia • Some suggestions for clinda to decrease toxin A from clostridia • carbopenem + clinda • vancomycin + aminoglycoside + clinda • Fluid replacement/ shock managment • Surgery a. < 3 hours preferable, but definitely < 12
Necrotizing Fasciitis - Outcomes • Very dependent to extent of involvement and time to diagnosis. • Mortality of 15-65% • Some suggestion of improvement with hyperbaric oxygen
Necrotizing Fasciitis Take Home Points Sharply demarcated erythema Pain out of proportion to exam Central anesthesia Rapid spread Get the surgeon fast!
Specific Diseases Not to Miss Second Case • 14 yo male develops malaise, fever, headache, and nausea. 12 hours later he develops lethargy, confusion and delirium. • In your ED he complains of headache before he becomes aphasic and seizes.
Encephalitis Cerebritis Meningitis
Encephalitis - onset • Usually have a prodrome of • Fever • HA • N/V • Lethargy • Myalgias • Present with altered mental status and possibly focal neuro deficits • behavior and speech changes are common
Encephalitis - usual suspects • HSV – reactivation • Arbovirus – ticks or mosquitoes • Rabies – mammal • VZV, CMV, Toxo – immunocompromised patients • Geography matters: SLE, EEE, WNE, JE, etc.
So if you suspect it… • Start Acyclovir for HSV or VZV • WE FORGET THIS STEP VERY OFTEN • Low risk drug • Without treatment, HSV mortality 50-75% • With treatment, 30% mortality • Mortality higher in <1yo or >55yo • VZV potentially lethal in immunocompromised patients • Toxo and CMV are treatable but less aggressive
The LP • Antivirals are OK before LP • PCR for HSV available • Specific 100%, sensitivity 75-98% • Viral serologies for arbovirus, SLE, JE, WNE • Toxo titers • Persistent RBC in CSF • Gram stain negative
Clinically, watch for: • Cerebral edema a. possibly helped by lasix, dexamethasone, hyperventilation • Shock, hypoxia • Hyponatremia (SIADH) Imaging only helpful to evaluate safety of LP and look for other causes
EncephalitisTake Home Points Long prodrome followed by rapid neurologic deficits – especially speech Acyclovir for meningitis patients Watch for cerebral edema and SIADH
Specific Diseases Not To Miss Third Case 20 y.o. CF just arrived home from college and presents with headache for one day. Mom thought she was under stress until she got a fever and had AMS.
Meningitis • Common bacteria are evolving rapidly. • Most common in adults: • Strep pneumo • Neisseria meningitides • Listeriamonocytogenes
What do we all know? • Rapidly fatal – especially if untreated a. Increase mortality with age>60, seizures, and severe AMS • Treatment should proceed LP
First controversy • CT before LP or just LP? Definitely CT if a. >60 b. AMS c. abnormal neuro exam d. hx of cancer/immunocompromize e. papilledema
Second controversy Corticosteroids? Early reports: no mortality benefit Later: decrease complications (especially hearing loss, brain damage, learning disabilities and retardation)
Third Controversy • Who gets prophylaxis? • Members of the same house or daycare • Those with direct contact of oral secretions • Current Regimens • Cipro – 400mg PO once • Rifampin – 600mg PO q12 for 4 doses
Why are we using vanco for everyone? • HiB vaccine shifted causative agent • Increasing prevalence of PCN and cephalosporin resistance • So… for everyone >1month, they get vanco • Supported by AAP, IDSA
Some quick abx facts • <1 month – S. agalactae, E. coli, L. monocytogenes, Klebsiellas • no ceftriaxone • Amp + Cefotaxime, Amp + aminoglyc • HSV coverage
Kids 1-23 months • S. pneumo, N. meningitides, H. infl, S. agalactae, E. coli • Easy coverage for all: • Vanc + 3rd gen cephalosporin
2-50 years old • S. pneumo, N. meningitides • Easy treatment • Vanc + 3rd gen cephalosporin
50+ S. pneumo, N. meningitidis, L. mono and aerobic GNB Vanc + 3rd gen cephalosporin If history of recent gram negative infection, change 3rd generation to cefipime
Take home points: Meningitis Treat early and with low suspicion Consider skipping CT’s in VERY selected patients Consider a loading dose of decadron Vanco with 3rd generation cephalosporin for >1 month old
So in summary Lots of rapidly fatal infections out there Most are detectable early Early treatment converts many of them to less fatal infections
Take home points: • Necrotizing Fasciitis – Pain/Fever OOP or anesthesia • Encephalitis – Get acyclovir early in suspected CNS infection • Meningitis – steroids, early abx