Infection Syndromes

odontogenic infections

25% of americans over 60 are edentalous because of these infections flow of saliva is critical in preventing infection and meds/acute illness are examples of contributors to diminished flow can cause gingivitis, peridontal infections can cause retropharyngeal abscess (fever, +/- sore throat), peritonsilar: fever and throat pain with bulging tonsil and displaced uvula organisms causing these infections are oral colonizers like strep viridans, HACEK and even staph aureus

Salmonella typhi

Causes typhoid fever: fever, HA, rose spots on abdomen, ab cramping Can remain in gallbladder chronically.

fever, lymphadenopathy

EBV: infectious mono CMV toxoplasmosis HIV malignancy

culture negative endocarditis

HACEK: now almost always identified with modern blood culture technology coxiella (agent of Q fever): think cattle/sheep, raw milk bartonella: cat scratches, homeless pt with louse chlamydia: pneumoniae species legionella: water exposure, air conditioning aspergillus: immunocompromised

major criteria for ARF

JONES i.e. joints: arthritis, carditis/MR/AR/pericarditis/myocarditis, nervous system (chorea), erythemia marginatum, subq nodules rash usually stimulated by hot water; looks kind of like lyme

acalculous cholecystitis

consider in pt critically ill in ICU long term with new fever and elevated alk phos and/or bili

endocarditis diagnosis

duke criteria: definitive IE via histology or culture showing infected valvular vegetation or abscess OR 2 major criteria/5 minor criteria/1 major and 3 minor

Chikungunya

febrile illness characterized by arthralgias very similar to dengue pain can last for years

genital ulcer disease: common in US

herpes simplex: painful, serpingous border, episodic recurrences, maybe lymphadenopathy syphilis: painless, hard coin like chancre; may be inapparent uncommon manifestation of syphilis: primary syphilitic chancre on tongue

cholangitis

infection of biliary ducts either intra or extra hepatic

viral exanthems

measles rubella parvovirus roseola

parvovirus

rash is slapped cheek and diffuse distribution of a lacy, reticular rash polyarthralgias often accompany the rash parvovirus can also cause a polyarticular small joint arthritis anemia or red cell aplasia (AIDS, sickle cell, other hemoglobinopathie) fetal hydrops and miscarriage

Vibrio vulnificus associations

shellfish and saltwater

endocarditis microbio

strep 60-80%: viridans group **, enterococcus, bovis, others strap (25-45%) with aureus more than coag neg 5-20% culture negative with most common etiology of this being prior abx use i.e. inadvertently sterilizing cx --> get blood culture before empiric abx

microbio of acute bacterial sinusitis

strep pneumo (over 40%), H flu, Moraxella, staph aureus, anaerobes, other strep species rare complications of untreated bacterial sinusitis are heralded by vision changes, periorbital swelling; location of sinus determines what complication occurs

enteroviruases

three families: echovirus, coxsackie virus, and enterovirus enteroviruses most typically causes nonspecific febrile illness that may or may not be accompanied by nonspecific rash (usually morbilliform) and also notably is common cause of aspetic meningitis and viral encephalitis less commonly, hand foot mouth disease with coxsackie much less commonly, can cause myocarditis or pericarditis that can result in dilated cardiomyocarditis

endocarditis major criteria

1) positive blood cultures: blood cultures positive for organism that usually causes endocarditis from 2 sep blood cx drawn at 2 sites at same time; persistent positive blood cultures drawn 12 + hrs apart of 3 at same time; blood cx positive for coxiella 2) echo positive for infection endo via TTE or TEE 3) new valvular regurg (increase or change from an already existing murmur not sufficient)

Fournier's gangrene

A serious infection of the subcutaneous tissues of the peritoneum eschar usually which is area of black skin often a decubitus ulcer i.e. bedsore and often in the genital area often in pts with poor control of blood sugars

signs and symptoms of biliary tract infections

RUQ pain and tenderness and positive murphy's sign inflammation can be present without infection, but watch for fever and elevated WBC as signs that you should get blood cx and treat with antibiotics diagnosis is via ultrasound which will show inflammed wall and pericystocholic fluid or cholescintigraphy if US not conclusive GV will need to be removed surgically if infected and usually try to calm down inflammation for several days with antibiotics before surg and acalculous needs drainage with biliary drain organisms include enteric GNR like e coli and klebsiella complications are that it can progress to perforation or hepatic abscess if not drained

Ricketssia rickettsii

Rocky Mountain Spotted Fever fever and a rash that can be desquamating that starts on palms on soles and is characterized by petechiae and purpura dog tick

arboviruses

SLE and VLE in americas west nile virus: africa, mediterranean, now US dengue yellow fever

pyelonephritis

UTI bacteria ascends to infect kidney parenchyma usually more sick than UTI with systemic signs of infection including high fever and malaise same organisms as UTI i.e. enteric GNR usually diagnosis: PE with CVA may use different abx and will treat longer i.e. 14 days complications: nephric or peri nephric abscess; kidney stones may become infected and are common cause of relapsing UTI (if staghorn calculous made of struvite think proteus infection which are urea splitting organisms)

varicella vs small pox

VZV occurs in crops of vesicles of different stages and smallpox vesicles all appear to be in same stage of development

cervicitis

a cause of vaginal discharge (vaginitis) / cervical discharge of mucopurulent or purulent fluid cervical motion tenderness with no adnexal or uterine tenderness NG or CT

paronychia

abscess adjacent to the nailbed

microbio of CNS infections

acute meningitis: S pneumo, N meningitidis, H flu B, group B strep, listeria and viral causes include arbo and enteroviruses meningitis chronic: neurosyphilis, borrelia burdorferi, TB, crypto/histpo/coccidio acute encephalitis: all viral including arbo, entero, HSV, and ZVZ chronic encephalitis: syphilis, borrelia burforferi acute/subacute bacterial abscess: staph, strep pyogenes, enteric GNR, mixed aerobic/anaerobic flora chronic brain abscess:m TB, cryptococcoma, toxoplasma, teania solium

Ehrlichiosis/anaplasmosis

acute tick borne febrile illness with fever, headache, malaise, arthralgias, shock, renal failure and GI bleed one species infects monocytes and other granulocytes but similar illnesses diagnosis: direct exam of peripheral smear buffy coat may reveal morulae in infected white cells which is rare but very specific for Ehrlichia serologic/antibody testing of acute and convalescent titers often required always give doxy often see transaminitis and thrombocytopenia which distinguishes from RMSF rash often absent i.e. spotless fever

distinguish common cold from

allergic rhinitis: more prolonged than viral infection; may be seasonal and predictable; no benefit from abx strep throat: GAS: fever, absence of cough, presence of tender anterior cervical adenopathy, exudate on tonsils; treat with penicillin to prevent post strep non infectious complications bacterial sinusitis: more prolonged, fever may be present and headache/congestion usually unilateral; may require abx pertussis: prolonged cough for more than 5-6 weeks, abx given to decrease infectiousness, but may not alter clinical course influenza: fever, myalgias, retroorbital headache are features that can distinguish flu from common cold

osteomyelitis treatment

avoid empiric therapy: treatment is not an emergency and should wait for definitive micro diagnosis unless pt very sick bone biopsy for culture to direct choice of abx ability to get bone bx limited by structural requirements (stability): removal of a piece of bone may compromise integrity of it impacting function long term and high dose abx for 6-8 weeks or more debridement and complete removal of infected bone may be curative ; if culture and pathology of proximal margin is negative, long term abx may not be needed

other notable causes of vaginitis

candida: not STD that presents with pruritis, cottage cheese discharge, and no odor trichomonas vaginalis: STD that presents with profuse, thin, grey, foul/fishy discharge bacterial vaginosis: not STD that is alteration of normal flora (lactobacillus) to other spp presenting with pruritis, thin discharge, fishy odor point of care testing of discharge important for making diagnosis complications: reiters, facilitates HIV, infertility, PID

infections of or originating in the skin

cellulitis lymphangitis necrotizing infection of skin and soft tissue furuncles and carbuncles blood stream infection : catheter related and endocarditits osteomyelitis septic arthritis

genital ulcer disease uncommon in US

chancroid: soft chancre, painful, may develop lymph node swelling with pus in them lymphogranuloma venereum caused by chlamydia trachymia trachomatis 1,2,3: ulceration of inguinal nodes, not genitals; proctitis in MSM outbreaks donovanosis (granuloma inguinale caused by klebsiella granulomatis): scarring inflammation of lymphmatics causing swelling of legs

varicella zoster

chicken pox febrile illness progression of rash from macules to papules to vesicles to pustules which then scab over --> once lesions are scabbed over, pt is no longer infectious to others varicella zoster (shingles) is a reactivation of VZV that typically occurs in dermatomal or disseminated and can also cause varicella zoster encephalitis or pnuemonia both syndromes can be prevented by vaccination

surgery for endocarditis

class 1 (surgery indicated): paravalcular abscess, CHF that is unresponsive to med management, organisms that cannot be optimally treated wtih abx class II: recurrent emboli and persistent vegetations despite abx therapy class III: mobile vegetations larger than 10 mm with or without emboli

C diff

colitis that may be mild, moderate or severe and almost always after abx pathophys: antibiotics kill the infection that we are targeting but also kill off good commensal bacteria --> C diff causes mucosal inflammation (not transmural) which is known as pseudomembranous colitis symptoms: diarrhea but can become severe colitis and toxic megacolon can occur; signs of severe colitis include WBC over 40, renal failure, lactic acidosis, fever diagnosis: toxin detection, PCR treatment: oral or IV metronidazole, oral vanc, but IV vanc --> if recurrent, fecal transplant

UTI organisms

colonize the perineum urinary bladder via functional integrity of urethral sphincter is essentially sterile UTI occurs when bacteria breach the sphincter and enter bladder and bacteria are not flushed out by bladder with micturition think enterobactericiae: klebsiella, e coli, enterobacter enteric GNRs adhere to epithelial cells

mechanisms of catheter related infections

contaminated catheter hub (endogenous from skin flora or extrinsic via HCW hands), contaminated infusate (fluid, meds or manufacturer), and skin organisms presentation: fevers/chills/rigors in pt with catheter and some pts will demonstrate redness around catheter and some don't

clinical course of urethritis

diagnosis: urethral swab or urine specimen for PCR; culture necessary for susceptibilities (GC) treatment: empiric treatment always treating for chlamydia --> if gram stain shows GC, treat that too and tx for chlamydia will also treat mycoplasma and ureaplasma complications: reiter's syndrome (reactive arthritis), facilitates acquisition of HIV, infertility, epidymitis, prostatis

endocarditis symptoms

fever (90%), myalgia, ab pain, headache, chills, anorexia, night sweats, back pain acute IE: high severe, SICK, consider staph aureus but can be other subacute: low grade fever, slow indolent course, not as sick, consider strep viridans

minor criteria for ARF

fever, arthralgia, elevated ESR or CRP prolonged PR interval on EKG

appendicitis clinical course

fever, elevated WBC are indicative of advancing infection --> send blood cultures before starting empiric antibiotics diagnosis: CT abdomen and pelvis treatment: always give abx and IV fluids appendectomy vs conservative management with no surgery is contraversial if no perf but surg still recommended and if perforation, emergent surgery

fever with zoonotic exposure

francisella tularensis: rabbits and squirrels --> wound with central eschar bartonella: cat scratch disease --> febrile illness with lympadenopathy pasteurella: cat bite leading to rapid local cellulitis which may be associated with blood stream infection brucella: livestock and raw unpasteurized milk --> fatigue and low grade fever developing into osteomyelitis and endocarditis yersinia pestis: prarie dogs or squirrels --> bubonic plaque, pnuemonia plague and DIC with necrosis/sepsis coxiella burnetii: sheep, parturient cats --> fever, pneumonia, and hepatitis leptospira: rats and mice --> hepatitis, fever, pneumonia, jaundice, conjunctival suffision etc.

meningitis spinal fluid analysis

glucose less than 20: bacterial, TB, fungal protein more than 250: bacterial and TB portion between 50-250: viral, lyme, neurosyphilis total WBC more than 100: bacterial meningitis total WBC between 100-1000: bacterial, viral, encephalitis total WBC less than 100: viral, TB, neurosyphilis, encephalitis, early bacterial opening pressure typically elevated at 35 cm H20 in bacterial neutrophil predominance in bacterial and early non bacterial

measles

incubation of 7-14 days cough, coryza, conjunctivitis stepwise increase in fever rash about 3 days after onset with centrifugal spread head to feet, maculopapular to confluent --> rashes described as morbilliform are measles like and are usually drug rashes individuals who are not protected against measles are infants who are too young to have been immunized, persons who were vaccinated with inactivated vaccine, etc.

PID

infection in any or all parts of female GU tract always starts with STD like GC or GT, but bacterial form vaginal area ascend when infection occurs and becomes polymicrobial with e coli, group B strep and anaerobes presentation: non specific lower ab pain, may or mat not have fever exam: cervical motion tenderness and adnexal /uterine tenderness --> sometimes liver capsule can become inflammed = perihepatitis workup: GC/CT testing and preg testing complications: infertility, tubo-ovarian abscess, increased risk of ectopic pregnancy

cholecystitis

infection of gall bladder and biliary tract usually associated with gall stones causing common bile duct obstruction i.e. calculous cholecystitis

Myiasis

infestation by fly larvae very rare but should be considered when people have traveled to central or south america human botfly

thromboplebitis

inflammation of a vein associated with a clot common at sites of prior IV lines, superficial veins can form clots can lead to pain and sometimes redness if superficial: usually treat with warm compresses to dissolve clot can progress to surrounding cellulitis which would require abx think staph aureus, strep species, coag neg strep

ARF treatment

irradicate GAS: PCN or amoxicillin to them and household contact anti-inflammatories: aspirin (although not usually in kids due to Reye syndrome) secondary proph: GAS treatment until age 18-21 in kids or 5 years if adult

fever of unknown origin

lasts longer then 2-3 weeks infection: most common infections causing FUO are endocarditis, occult abscess, undiagnosed HIV, and TB; other causes can be plentiful and a careful exposure history is important in diagnosis malignancy: particularly heme and of solid tumors those affecting liver (primary or mets) and renal cell cancer most likely to cause fever collagen vascular disease: in young ppl, most likely lupus, RA or still's disease and in elderly most likely polymyalgia rheumatica or temporal arteritis other which includes drug fever, PE or DVT and familial med fever/other periodic fever syndromes

Borrelia burgdorferi

lyme disease prevalent in NE and NC US via deer tick (Ixodes) and usually the nypn has to feed for 1-3 days stage 1: acute localized to skin stage 2: disseminated with generalized rash, peripheral like bell's palsy or central (meningitis) nervous system; cardiac conduction defects; large joint swelling stage 3: joints, CNS, radiculopathy treatment is with oral abx (doxy) if CNS not involved and if it is ceftriaxone may exhibit jarisch-herxheimer reaction

appendicitis PE findings

mcburneys point tenderness rovsings signs: palpate LLQ and there is referred pain to RLQ psoas sign: pull leg bag to irritate appendix that sits on top of psoas

lymphangitis

microbio is same as clelulitis spread of infection into lymph system treat more rapidly than cellulitis

common cold and complications

microbio: rhinovirus, coronavirus account for 2/3 and others include mild infections of influenza, parainfluenza, RSV, adenovirus, and enterovirus transmission: hand contact of infected secretions, incubation period of 8-24 hrs, most resolve 7d and 25% resolve by 14d complications: 1)acute sinusitis with viral resolving in 7-10 days with no abx and acute developing in 1% of cold cases due to impaired mucociliary function with 75% of cases resolving without abx within 4 weeks --> less than 7-10 days no abx and more than 10 days consider abx 2) otitis media: viral OM develops in 1/3 of colds and bacterial in 10% and identified due to building tympanic membrane with pus behind 3) asthma exacerbation 4) pneumonia

rubella

milder disease than measles with milder rash significance in perinatal infection (congenital rubella syndrome: ears, eyes, heart etc) and less so a febrile illness

zika

mosquito or sexual partners who are infected symptomatic only in 20-25% developing fetus: microcephaly and miscarriage complications: guillain-barre, encephalitis

yellow fever

mostly africa and south america sudden onset febrile illness with HA, myalgias, jaundice and hypoalbuminemia with anuria

acute meningitis microbio

neonatal: pneumococcus, meningococcus, group B strep, entergic GNR, listeria age 1-18: pneumococcus, meningococcus and enterovirus for viral age 18-60:pneumococcus, meningococcus and for viral: enterovirus, HSV2, HIV, west nile virus, arboviruses age 60+: pneumococcus, meningococcus, listeria and for viral enterovirus impaired cellular immunity: pneumococcus, meningococcus, listeria

mumps

no rash highly infectious droplet spread with 16-18 day incubation period and highly infectious 3-7 days before any symptoms fever, headache, fatigue anorexia 38 hours before salivary gland swelling usually parotid unilaterally 15-30% of men get unilateral epidydimoorchitis: fever with testicular pain about 5-10 days after salivary gland swelling --> of these about half develop some degree of testicular atrophy and can be severe enough to impair fertility 5% of women develop oopheritis other complications: meningitis, encephalitis, sensorineural hearing loss

classification of joint effusions

normal: clear/colorless and viscous with leukocyte count of less than 200 noninflammatory: clear, yellow and viscous with 200-2000 leukocytes inflammatory: cloudy, yellow with decreased viscosity with 2-100K leukocytes septic: purulent with markedly decreased viscosity with 50K + leukocytes that are more than 95% polys

bloodstream infections

origin: central venous catheters, skin and soft tissue infections or severe infections in almost any organ system symptoms: fever, rigors, symptoms of primary infection consequently can sometimes lead to endocarditis --> mag of infection amplified with signs/symptoms of endocarditis as well as high grade bacteremia

UTI diagnosis

outpatient: dysuria and frequency has sensitivity of 90%; can do dipstick or not which will show presence of nitries and leuk esterase urine culture indicated in complicated inpatient: always get full UA with microscopy in pts with new fewer, looking for pyuria i.e. 10-20+ WBC per hpf --> if there are 0-5 WBC, no UTI no matter what grows on urine culture asymptomatic bactuiria: bacteria with no pyuria --> no treatment except pregnant women, anyone undergoing urologic procedure, early after renal transplant i.e. first month or so

Osler's nodes

painful nodules on finger and toe pads seen in endocarditis

janeway lesion

palmar or plantar erythematous or hemorrhagic papule(s) associated with infective endocarditis; also associated with Osler's nodes

brain abscess

pathogenesis: bacteria enter brain parenchyma by direct spreac or hematgogenous seeding clinical: headache in 65-70%, fever in 50%, nuchal ridigity in 10%; focal neuro signs or depressed mental status can develop with time; pt may have obvious source of infection or may be otherwise healthy

meningitis

pathogenesis: balance of secretion/reabsorption of CSF is disrupted by inflammation (bacteria or inflammatory cells disrupt giant vesicles that transport fluid in arachnoid villi) --> volume and pressure increase steroids play role in treatment to decrease inflammation clinical: rapid onset of fever, nuchal rigidity, and lethargy; headache and photophobia also typical; seizure and focal neuro deficits are late complications prompt recognition is key: mortality is 25% with CSF analysis predicting etiology; give abx coverage within 30 minutes of presentation to ED

encephalitis

pathogenesis: exclusively viral; viral tropism determines localization to and within the brain, disrupting neuronal processes clinical: can resemble meningitis, but lacks nuchal rigidity; in meningitis, cognitive/cerebral function is normal but in encephalitis, cerebral function is abnormal with sensory/motor deficits, behavioral changes or cerebellar dysfuction; may also present with lethargy treatment: most cannot be treated except for HSV and VZV which respond to acyclovir usually acyclovir is given until results of PCR testing of CSF for these are available; failure to give antivirals in this setting increases mortality **temporal enhancement** buzzword for HSV

osteomyelitis

pathogenesis: hematogenous usually staph aureus or skin organisms, usually single organism, often develops in area of prior injury OR contiguous with local spread e.g. diabetic foot ulcer or traumatic injury usually with multiple organisms to blame and related to flora of source area symptoms: may be non specific, fever, chills or may localize to infected bone' can be acute and sick or subacute and indolent diagnosis: radiographic imaging often need more than plain films which may be negative for up to two weeks after onset; MRI is best test if available; a sequestrum may be visible (dead bone), microbio via bone biopsy is essential need to treat more intensely and longer so need to understand if bone is infected

septic arthritis

pathogenesis: often hematogenous from distant source synovium is closed space that is restricted anatomically so inflammation causes pressure and therefore pain suboptimal treatment can severely impact joint function in future clinical: red, hot, swollen, painful joint; aspiration of fluids helps distinguish aspectic from septic; arthritis is not arthalgia with many infections being accompanied by arthalgias

types of lines

port: surgically implanted and it is a reservoir under skin that is accessed by special needle when med needs to be administered hickmann: surgically implanted line emerging from subclavian vein via exit site on anterior chest (this makes it more likely to be infected than port) PICC line: peripherally inserted central catheter that are inserted in procedure unit via cephalic or basilic vein and extends through CVS into RA midline cathethers: shorter than PICC lines and more convenient to place

Molluscum contagiosum

poxyvirus in kids: very common esp in day care centers adults: STD usually rounded edges with central umbilication treatment: cryotherapy or curettage

endocarditis minor criteria

predisposing herat condition of IV drug use fever more than 100.4 vascular phenomenon: major arterial emboli, septic pulmonary infarcts, mycotic aneursym, intracranial hemorrhage, conjunctival hemorrhage, janeway lesion immune complex phenomenon: GN, osler's nodes, roth spots, elevated RF positive blood cultures that don't meet the major criteria def

diverticulitis

presentation: older pts usually with acute LLQ pain and diarrhea or constipation, progression to fever and systemic signs of infection organisms: enteric gram negative rods/anaerobes diagnosis: CT ab/pelvis treatment: abx if no perforation or small perforation and if no improvement or worsening symptoms or CT, need partial sigmoidectomy with temporary ostomy

acute rheumatic fever

presents similarly to endocarditis, but different syndrome presents weeks after group A strep infection rare in US due to abx for sore throats but consider in someone who traveled to areas without access to abx symptoms: fever, aortic regurg or mitral regurg murmur, rash, arthritis diagnosis: preceding GAS infection with 2 major and 1 major/2 minor criteria with infeciton determined via throat culture, rapid strep Ag test, ASO titer or ADB titer if hx of ARF in past, it can recur: 2 major, 1 major plus 2 minor and 3 minor

prostatis

prostate can become infected with bacteria in two ways: ascending infection with UTI or gonorrhea/chlamydia and hematogenous spread i.e. staph infection acute symptoms: similar to UTI but also difficulty with urinary stream due to prostatic swelling, usually more sick, high fever diagnosis: digital rectal exam for tenderness, consider STD eval and urine culture treatment: distinguish between URI and prostatic because prostatis is treated longer for several weeks up to 6 weeks or longer in at risk pts, TB is something cause of chronic prostatis

necrotizing infections of skin and soft tissue

results in necrosis and loss of tissue and pace of illness is very aggressive microbio: can be caused by one organism i.e. strep pyogenes, clostridium perfringens and staph aureus or pseudomonas, enteric GNR, vibrio vulnificans) or several (polymicro infeciton which typically includes streps, gram neg rods and anaerobes) characteristic findings: pain out of proportion to findings (either much greater earlier in course or much less later due to destruction of peripheral nerves); tense edema with presence of hemorrhagic blisters/bullae in a case that appears to be cellulitis due to infection of deeper tissue planes; presence of crepitus which is sound or tactile sensation of crackling in involved limb indicating presence of gas risk factors: severe DM, severe trauma, infection drug use esp with use of pitch tar, obesity treatment: urgent surgical debridement with abx playing secondary role

females and UTIs

short urethra and proximity to anus vs long and prostatic secretions with antibacterial properties sexual intercourse, incomplete bladder emptying, neuromuscular disease, prostatic hypertrophy obstructs the urethra bacteria do not invade mucosa in lower tract UTIs so minimal inflammatory response and no systemic symtpoms (no fever) --> symptoms due to spasm: urgency, frequency, dysuria

fever and salivary gland swelling ddz

sialadenitis: infection of salivary gland with oral bacteria; staph/strep most likely often associated with stone in salivary duct: sialolithiasis viral infections: mumps, HIV,EBV, CMV autoimmune: sjogrens, sarcoid malignancy

epididymitis

similar to prostatis, usually occurs as ascending infection or UTI or G/C classically men under 35 yo more likely STD and older more likely UTI acute symptoms: acute onset scrotal pain, fever, need to differentiate from torsion diagnosis: physical exam, UA or urine culture, urine gonorrhea and chalmydia testing

furuncle vs carbundle

single abscess vs multiple together micro bio: usually staph aureus and less likely enteric GNRs treatment: drainage is necessary since center of abscess cannot be penetrated by abx and it is composed of dead organisms and polys so body's response to this is to wall it off with fibrous capsule abx often secodnary

roseola

sixth disease; HHV6 in kids 3 months to a few years, high fever (105) precedes a diffuse, centripetal rose-colored rash self limited it can cause encephalitis in bone marrow and solid organ transplant pts (usually reactivation from latent infection)

cellulitis

skin colonizers become the pathogen most skin: staph (aureus and coag neg) and strep (group A andothers) axilla and groin: staph, strep as above, plus enteric GNRs and anaerobes micro: strep pyogenes (grp A) >> staph aureus > enteric GNR, anaerobes +/- pustular presentation with pustular probably being staph and non pustular probably being strep

Lemierre syndrome

some bacteria can form deep space infections in the carotid sheath typically high fever with sore throat CN 9, 10 and 12 travel in carotid sheath clot can form in jugular vein which is infected and can lead to septic emboli bacteremia present so check blood cultures almost always caused by fusobacterium necrophorum

toxic shock syndrome

staph aureus or strep pyogenes superantigens overstimulating immune system conjunctival injection, blanching erythematous rash, desquamating rash

microbio of septic arthritis

staph aureus, strep pyogenes, enteric GNR, any organism gonoccal infection can be part of systemic syndrome (pustular skin lesions, tenosynovitis and arthralgias or as purulent arthritis with or without skin lesions) lyme arthritis: recurrent attacks of arthritis in weight being joints that may persist despite appropriate therapy and may also resolve without treatment rare: hep B during prodrome, parvovirus prior to or during rash; anthropod borne viruses like chikungunya treatment: pathogen specific, may need repeated washouts for optimal debridement

complicated UTI

structurally abnormal urinary tract and more likely to spread to upper tract and cause pyelonephritis stones which can act as nidus for recurrent UTI or cause obstruction; indwelling foley; obstruction by tumor; VUR in children (vesicourethral reflux); pregnancy with dilation and decreased peristalsis of ureters; men? consider longer treatment and anatomic evaluation

dengue fever

sudden onset fever (returns every 1-2 days), headache (typically behind the eyes), varied GI, lymphadenopathy, leukopenia, thrombocytopenia, transaminitis, muscle / joint pain (source of the name "breakbone fever") - skin rash like measles dengue hemorrhagic fever - bleeding, low platelets (due to viral destruction of bone marrow), plasma leakage and shock Rash blanches under pressure southeast US or traveling

bloodstream infections and specific immunosuppression

terminal complement def (C5/C3): meningococcemia can develop in absence of syndrome of meningitis asplenia: infections with encapsulated organisms like pneumococcus, meningococcus and H flu much more likely to be associated with bactermia neutropenia: ANC of less than 500-1K: enteric GNRs will translocate from gut lumen into bloodstream casing symptomatic bloodstream infection

epstein bar virus

tonsillar swelling with exudate, kissing tonsils, really high fever, bad cervical lymphadenopathy and bad sore throat burkitt lymphoma; can cause post transplant lymphoproliferative disorders

endocarditis

transient bacteremia trhough daily activities or from another ifnected site bacteria stick to turbulent or abnormality in valve fibrin, platelets scar attach to bacteria and then more bacteria stick to plaque --> vegetation as body tries to bread down these products, bacteria leaks --> persistent bacteremia pieces of vegetation can break off to embolic sites 4-6 wks of abx

syphilis diagnosis

two step test: non treponemal with high sensitivity and low spec: RPR --> specific not not very sensitive treponema palidum Ab treatment is penicillin

adenovirus

typically presentation is URI or LRI with some serotypes causing GE or hepatitis pharyngoconjunctival fever: uncommon but dramatic presentation of several days of high fever, sore throat, severe conjunctivitis and lymphadenopathy finally, some serotypes can cause acute hemorrhagic cystitis which presents as gross hematuria

urethritis

urethral discharge of mucopurulent or purulent fluid with dysuria neisseria gonorrhea: discharge is purulent; gram stain of fluid with polys and gram ngative diplococci can disseminate --> rash and arthritis chlaymia trachomatis: discharge is clear or no discharge at all; gram fluid with polys but no organisms other causes: trichomonas vaginalis; mycoplasma genitalium; ureaplasma urealyticum

GE causes

vomiting: staph aureus 2-6 hours after ingestion, bacillus cereus, norovirus secretory diarrhea: salmonella, E coli, vibrio choleria and other vibrios, aeromonas hydrophilia; rotavirus, norovirus, adenovirus; giardia lamblia, cryptosporidium, cyclospora, strongyloides, microsporidium, isopora inflammatory diarrhea: salmonella, shigella, EHEC, campylobacter, yersinia, C diff, other vibrios, plesiomonas shigelloides, adenovirus, entameoba histolytica

ebola

zoonotic illness via fruit bats incubation of 2-21 days can lead to hemorrhagic fever but main thing is profuse volume loss (5L per day) via vom and diarrhea