Infectious Dz and Allergies/Immunology Flashcards
Things that can affect your dx with infectious disease
Season Age General health Fever Previous sx Exposure Travel Daycare Immunization therapy
Work up for infectious dz- general
CBC -Left shift in CBC means high neutrophils can include bands -Right shift is high lymphoctes Gram stain Cultures LP Rapid screening test PCR (DNA, RNA) Imaging
DDx- viral- ID
Petechiae
Neutropenia
Lymphocytosis
DDx- bacterial- ID
Petechiae Purpura Leukocytosis- left shift Neutropenia Increased ESR/CRP
What does secondary prophylaxis include?
Meningococcus
Tetanus
-Dirty wound, give if they have not had shot within 5 yrs
-Clean wound, give if they have not had the shot within 10 yrs
Rabies
-Immunoglobulin, inject into wound as much as you can, then give IM injection
-Day 1, 3, 7, 14 for vaccine schedule
-Try to find the animal
-Document if they decline
Fever without source: 1-3 mos
Viral Bacteremia -GBS -E. coli -Listeria monocytogenes UTI -E. coli Pneumonia -S. pneumoniae -S. aureus Meningitis -S. pneumoniae -HSV -Enterovirus -N. meningitidis Bacterial diarrhea -E. coli -Salmonella -Shigella
Fever without source: 3 mos- 3 yrs
Viral Occult bacteremia - Greater than or equal to 102.2 -WBC > 15K -Left shift -Increased ESR/CRP UTI -UA, URC, BLDC
What to do with < 3 mos with fever?
Usually do an LP
Neonate: run your basic tests: BCx, CBC, CXR, urine
You don’t usually see strep in _____
< 2 yo
Will see URI, OM
Fevers of unknown origin
Infections Inflammatory dz -15% Malignancy -10% Fictitious
Fever and rash in peds
Macular/maculopapular -Usually measles or rubella Diffuse erythroderma Urticarial Vesicular, bullous, pustular Petichial-purpuric Erythema nodosum
Characteristics of measles
Papular lesions of trunk, neck, face
Red watery eyes
Grey-white spots in the mouth
Characteristics of rubella
Typically lasts around 3 days Body aches Anorexia HA Pharyngitis Conjunctivitis Low-grade fever Highly contagious, but resolves on its own
Characteristics of roseola infantum
HSV 6 and 7
Abrupt fever, rose-colored maculopapular rash lasting 3-5 days
Cough
5ths dz- characteristics
"Slapped cheek" Caused by parvovirus B19 Usually occurs during springtime Diagnose with PCr Reoccurs with bathing, rubbing Mild anemia, lymphopenia
Tx for herpes zoster
Antivirals and pain meds
Give hydrocodone at hospital but not for the 4 wks that you’ll treat it
Varicella zoster
Do not give ASA or acyclovir
Could develop post-secondary staph and strep infections with scratching and dirty fingernails
Give the vaccine at 12-15 mos and 4-6 yrs
-85% effective in preventing dz
-95% effective in reducing severity
Impetigo characteristics
Bolus impetigo has clear fluid-filled cysts
Crusting, yellow, honey-crusted
See on Gram stain: purple (Gram pos) cocci in clusters
Give 2% mupirocin
Cellulitis
Demarcate with a pen, tell them to come back in 24 hrs to the ER
Look for LAD, check above and below
Is there any fluctuation in the wound? Do you want to I and D?
Shot of Rocephin, then diclocycillin or Keflex
Erysipelas
Just dermal area, not full thickness
Line of demarcation is very clear
Causative agent is group A strep
If IC or DM, try to convince hospitalist to admit
Forunier’s gangrene
Caused by staph, strep, clostridium
Very quick progression
Need immediate surgical consult
IV clinda, surgeon may add aminoglycoside, may also use Rocephin
Folliculitis
Affects follicles of hair cells
Pseudomonas, staph are causes
Chlorhexidine 1% or clinda cream
Ringworm
Use KOH prep to diagnose Will see budding, septate or aseptate hyphae Treat with miconazole, clotrimazole Takes time to heal Use a thin layer, and keep it dry
Herpetic whitlow
Pruritis and pustules
Valacyclovir
Herpes gladitorium
Worry about eyesight
Do a slit lamp exam and document when it doesn’t affect the eye
Otherwise, you need to call an ophthalmologist
HPV vaccine
Give between ages 9-26
Quadrivalent covers 6, 11, 16, 18
3 doses
98-100% effective
Molluscum contagiosum
Cause is pox virus
Fleshy, skin-colored lesion with dimple
Self-limiting over several mos
What can be seen on a blood smear with mono?
Atypical lymphocytes
Cat scratch or bite
Could affect epitrochlear LN
Boggy
Caused by Pasturella multocida
Give Augmentin
M. Kansaii
Usually a post-surgical infection
Can also involve soft tissue
Found in TX, LA, FL, KS, IL
Treat with rifampin, methambutol
Encephalitis types
California St. Louis Equine West Nile -Occurs in summer in North America -Sore throat, fever, aching, lethargy, HA, behavior changes, neuro deficits
Encephalitis work up
Get a CSF test -Viral: nl glucose, slightly elevated protein -Bacterial: low glucose, high protein LP BCx CBC MRI
Mechanism of encephalitis
Infection
Immune-mediated response
Herpes is MCC of sporadic encephalitis in children
Colds
Antihistamines and decongestants are not recommended for children under 6 yrs
If no better in 10-14 days consider bacterial
Sinusitis
Get a water’s view CT
-Will show areas of exudate, inflammation, or possible Netty pot use
Causes are M. catarrhalis, H. flu, S. pneumoniae
With children, look for a FB
Look for fever, tenderness mucopurulent d/c in nare
Treat with Augmentin
Otitis media
If it’s happened too many times, refer to ENT for possible myringotomy
Difficult cases of otitis externa
If canal is really tight, use an earwick
Put liquid lidocaine on there before inserting it
Croup
Steeple sign on X-ray
Usually in fall and winter mos
Give dexamethasone
Consider racemic epi to reduce subglottic edema
Epiglottitis
See thumb print sign on X-ray
Hib, staph, strep are causes
Treat with tube, abx
Pertussis
B. pertussis Spread by cough Stages -Catarrhal -Paroxysms -Convalescent Peak incidence < 4 mos Typically seen in 1-10 yos Contagious for first few weeks Runny nose, low-grade fever WBC 20K Lymphocytosis of 75-80% Give azithromycin, clarithromycin
Bronchiolitis
Affects small bronchioles
Late fall to early spring
Runny nose, low-grade fever, cough
Leading cause of hospitalization in infants
ELISA to diagnose
Primarily caused by RSV
Hyperresonance on percussion with diffuse wheezes or crackles
PNA
Bacterial PNA is typically lobular
Not getting better, do another test, like a CT
Increased interstitial marking like tree branches indicates a viral infection
Treat with Z pack for CAP
Induce a sputum culture with a neb
Types of pneumonia
Atypical Bronchial SARS -Coronavirus PNA in the IC -Gram neg enteric bacteria -Virus -Fungi -Mycobacteria
PNA workup
CBC -Bacterial vs viral -Sputum gram stain and culture depending on child's age -Rapid viral antigen detection PCR Blood cultures CXR
DDx of PNA
CF AIDS Disorders of leukocytes Disorders of cilia -Kartagener syndrome- immotile cilia GERD FB
Complications of PNA
Abscess secondary to lung necrosis Empyema Effusion Bronchiectasis d/t scarring Penumatociles- thin blebs, air or fluid-filled, can sometimes pop Bronchiolitis obliterans -small airways are replaced scar tissue Sawyer-James syndrome -Severe necrotizing pneumonia -Increased translucency of lung -Adenovirus type 21
Tx of PNA
Do culture and MIC
S. pneumoniae MIC < 2- Ampicillin/PCN/amoxicillin
S. pneumoniae MIC >4- Ceftriaxone/Levoquin/Linezolid
Mycoplasma- Zithromycin
MRSA- Clindamycin or Vanc IV
HSV- acyclovir
Infective endocarditis
Reasons for kids to get this- wound that hasn't healed well or very infected, dental work Bacteria -Viridians step -S. aureus -Hemolytic strep A, B, C, G, D -Cause vegetation on valves, which become incompetent. Results in hemolyzing blood Fungi -Candida
Workup for infective endocarditis
ESR/CRP CBC BLDC RF/ANA- may be positive Echo- consider doing TEE instead of transthoracic- more sensitive
Complications of infective endocarditis
Emboli
Abscess
Aneurysm
Tx for infective endocarditis
Viridians strep- PCN G 4 wks
May consider Pen G plus aminoglycoside 2 wks
Surgery
Cure rate >90% in uncomplicated endocarditis d/t viridians
Acute gastroenteritis
Diarrhea
Leading cause of morbidity and common in US
Person-to-person contact
Contaminated food/water
If you see both nausea and vomiting at the same time, consider food poisoning
Acute gastroenteritis bacteria
E. coli Salmonella Shigella Vibrio cholera B. cereus- refried rice S. aureus- mayo
Acute gastroenteritis virus
Rotavirus
Adenovirus 40 and 41
Norovirus
Acute gastroenteritis parasites
E. histolytica
Giardia lamblia
Labs for acute gastroenteritis
BMP- worried about dehydration, look at electrolytes Sodium may be low CBC Fecal culture Ova and parasites
Tx of acute gastroenteritis
Bacterial: 3rd gen cephalosporin S. typhi
Parasite: Metronidazole
Virus: supportive
Hepatitis
Types A, B, C, D, E, G
A= poor hand washing
B+ D= chronic hep
-Could lead to fulminant hep, cirrhosis and CA
HBV and HCV
-IV drugs, maternal fetal, blood products/needle stick
Tx of hepatitis
HBV
-Interferon Alpha-2B or lamivudine
HCV
-Interferon or in combination with ribavirin
Most cases of acute viral hep resolve in time
-HAV and HEV- acute
-HBV, HCV, HDV= chronic, possible cirrhosis and carcinoma
UTI labs
Ensure clean catch UA URC Imaging if necessary -Could have stone or chronic kidney or bladder infections due to vesicourethral reflux Chlamydia culture if suspect
UTI possible origin in teens
Staph saprophyticus, chlamydia and E. coli 12-72 hours after intercourse
Causes urethral syndrome and urethritis
Vulvovaginitis
MC gyn in children
Causes of vulvovaginitis
Physiological leukorrhea- nl Non-specific: nl Bacterial -3 criteria: homogenous d/c, pH >4.5, a little fishy odor -Also see clue cells -Treat with metronidazole Candidiasis -Treat with metronidazole Enterobiasis- pinworms -Treat with mebendazole Giardiasis -Treat with metronidazole Molluscum contagiosum -Treat with curretage Phthirius pubis: crabs -Treat with permethrin Scabies -Treat with permethrin Staph/strep -Treat with dicloxacillin or 1st gen cephalosporin FB
UTI parenteral tx
Cephtriaxone or gentamycin
UTI oral tx
Cephalosporin
Augmentin
Septra/Bactrim
chlamydia
70% of women are asymptomatic Gram neg May lead to PID -Abd pain -Adnexal tenderness -Pain on cervical motion -Fever Tx -Rocephin + doxy or Azithro
Syphilis
Treponema pallidum
Great imitator
Primary-chancre
Secondary- fever, LAD, rash, condolomata lata lesion
Tertiary- organ damage, neurosyphilis, aorta
Diagnose with dark field microscopy
Tx of syphilis
Primary- 2.4 mil U pen G benzathine q2-4h x 10 days
Secondary: 2.4 mil u pen G x 3 wks (3 doses)
Tertiary: 3-4 mil U pen G q4h x 10-14 days
HSV
Pre-herpatic pain Vesicular HSV culture Rx -Acyclovir/Famcivlovir/Valacyclovir Post-herpatic pain lasts 3-4 wks Meds reduce recurrence by 75%
H. ducreyi
Bacterial
See chancre
Culture
Tx: Azithro 1 gm po
Granuloma inguinale
Cause is Klebsiella
Requires bx for staining
Tx: Doxy
Trichomoniasis
Vulvular inflammation 70% asymptomatic D/c- frothy bubbly Strawberry cervix Diagnose with KOH Tx: metronidazole
Candidiasis
Thick d/c with itch Candida albicans Consider DM/BCP/ current or recent abx KOH Fluconazole or nystatin for tx
Genital warts
HPV aka condylomata acuminata Firm grey to pink Cervical neoplasia or dysplasia HPV 16 and 18 (70% cancer) Tx: Podofilox or cryo
Type I allergy
Immediate
IgE
Anaphylaxis, angioedema, urticaria
Type II allergy
Cytotoxic
IgM, IgG, complement, phagocytosis
Cytopenia, nephritis
Type III allergy
Immune complex
IgM, IgG, complement, precipitins
Serum sickness, vasculitis
Type IV allergy
Delayed
T-lymphocytes
Contact dermatitis
Idiopathic allergy
Effector mechanism varies
Non-specific rash
Dx of allergies
Skin patch testing RAST (radioallergosorbent test) panels CXR CT sinuses Serum immunoglobulins
Allergic rhinitis
Eosinophilic inflammation of nasal mucosa
PE will show a transverse nasal crease
Eosinophils will be present in nasal secretions and elevated on CBC
Non-allergic rhinitis is more likely vasomotor, infectious, or secondary to a FB
Allergic rhinitis medications
Mild: antihistamines PRN
Moderate: routine administrations of LTRA (Leukotriene receptor antagonist)- Singulair (montelukast)
Severe: topical nasal steroid, immunotherapy, antihistamine, or LTRA
Systemic anaphylaxis
Rapid onset allergic reaction d/t the widespread degranulation of mast cells after crosslinking of IgE on the mast cell surface
Often secondary to bee stings, food exposures, or drug administration
Severe manifestations: airway obstruction, hypotension
Stings
Good to watch if you have FHx
Tx: Children younger than 16 with diffuse urticaria require epi
Children >16 are treated as adults and require subQ epi
Any child with a systemic rxn to a bee sting requires referral to an allergist
Any child with a life-threatening rxn to a bee sting requires venom immunotherapy which is 98% effective in preventing future rxns
Anaphylaxis therapy
Epi is primary
Antihistamines are secondary
For severe event steroids may prevent late-phase rxn
Angioedema
Hereditary angioedema: autosomal dominant d/o characterized by the absence or abnormal function of the C1 esterase inhibitor which results in increased vascular permeability
Angioedema related to allergic rxn: self-limiting, episodic, commonly triggered by minor trauma
Give benadryl, dexamethasone
Asthma causes
Allergens -Pollen, mites, animal dander, mold Irritants -Tobacco smoke Viral infections -RSV -URI Exercise
Allergy meds
Antihistamines -1st gen: sedation problems -2nd gen: preferred where sedation a problem LTRA -Similar efficacy to antihistamines Mast cell stabilizers Topical corticosteroids -Most effective, block more aspects of allergic inflammatory response
Allergic conjunctivitis
If bacterial, will have matted eyes, exudative drainage, whereas allergic has clear fluid
Acute or chronic, seasonal and perennial
Itching and excessive tearing
Tx is with saline eye drops and antihistamines
Causes of a cough in a child <1
CF Resp tract infection Aspiration Dyskinetic cilia Lung/airway malformation Edema
Long-term controlled meds for asthma
ICS LTRAs -Zafrilukast > 5 yrs BID -Montelukast QD --6 mos-5 yrs 4 mg --6-14 yrs 5 mg --15 yrs and above 10 mg
LABA
Relax airway smooth muscle No anti-inflammatory BID >5 yrs Maintenance Prevention of exercise-induced asthma
Omalizumab (Xolair)
Anti-IgE AB
Mod to severe asthma
12 yrs and older
SubQ q2-4 wks
SABA
Bronchodilator
Acts in 5-10 mins
4-6 hr duration
Prophylaxis
Ipratropium
Relieves bronchoconstriction
Decreases mucus hypersecretion
Reduces cough
Not for long-term use
Corticosteroids
Acute exacerbation
3-10 days
1-2 mg/kg/day then 1 mg/kg/day days 2-5
General tx principles in asthma
Step up-step down therapy
All children should have short acting MDI
ICS preferred for all children-persistent asthma
Rules of two;
-Sx 2 or more days/week
-Sx 2 or more nights/mo
Primary immunodeficiency
Refers to a group of more than 300 rare, chronic disorders in which the immune system fails toa ct appropriately
Red flags:
-Severe infections requiring hospitalizations at an early age
-Persistent or recurrent illnesses
-Infections secondary to obscure or uncommon organisms
Things to check with immunodeficiency
CBC to look for neutropenia or lymphopenia (SCID), esosinophils (allergic dz) or anemia (chronic dz)
Serum immunoglobulin levels should be obtained: IgG, IgA, IgM, IgE, IgD
DiGeorge syndrome
Partial immune defects with low T-cell numbers and functions that tend to improve with age
Known as velocardiofacial syndrome or catch 22 syndrome because of the Cardiac anomalies, Abnormal facial features, Thymic hypoplasia, Cleft palate and Hypocalcemia stemming from deletions in chromosome 22q11.2
Wiskott-Aldrich syndrome
X-linked disorder that results from defects in both cell-mediated and humoral immunity. There is a predisposition of lymphoproliferative disorders
Children presents with the triad of thrombocytopenia (low platelets), eczema and recurrent infections
Chediak-Higashi syndrome
Abnormality of secondary granule that results in defective neutrophil and NK cell function
Usually presents with partial oculocutaneous albinism
Most cases progress to a lymphoproliferative syndrome with generalized fever, jaundice, hepatomegaly and pancytopenia
Stem cell therapy
This is the only cure available for primary immunodeficiency
Stem cells are found in bone marrow, cord blood and peripheral blood
The main risk associated with stem cell therapy is GVHD
