Peds 9 Flashcards
What are the names of the 2 main Sulfonamide drugs
Trimethoprim
Sulfamethoxazole
Aka Bactrim
MOA of sulfa drugs
Block folate synthesis
Uses of sulfa drugs
- UTI
- Acute prostatitis
- Gram neg GI and UTI bacteria
- MRSA
- Nocardia
- Pneumocystis jirovecii pneuomonia
- Toxoplasma gondii
Adverse reactions of sulfa TMP/SMX
- Pancytopenia (due to inhibition of DNA synthesis)
- Megaloblastic anemia
- Teratogen (NTD)
- Allergic drug rx
- Hemolytic anemia is G6PD deficiency
- SJS
- Type 4 RTA
- Interstitial nephritis
- Photosensitivity
- Kernicterus
- Drug induced lupus
Names of Fluoroquinolone drugs
Ciprofloxacin, Levofloxacin, Moxifloxacin
MOA of Fluoroquinolones
Inhibits bacterial topoisomerase, such as DNA gyrase (relieves supercoiling)
Uses of Fluoroquinolones (broad)
Mostly gram negative but some gram positive
What type of gram neg infections are fluoroquinolones used for
- UTI (complicated - uncomplicated treated by TMP/SMX)
- Even UTI treated by Pseudomonas
- Pyelonephritis
- Acute prostatitis
- Gram negative gastroenteritis
- Gram neg osteomyelitis
What type of gram positive infections are fluoroquinolones used for
- Bacillus anthracis
- Community acquired pneumonia
- Atypical pneumonia (Mycoplasma and Legionella)
Adverse effects of Fluoroquinolones
- Prolonged QT
- GI (N/V/D)
- Tendon and cartilage damage to elderly and hose on chronic steroids
- Teratogen (damage to growing cartilage)
MOA of Metronidazole
Forms toxic free radical metabolites that disrupt bacterial DNA
In broad terms, what does Metronidazole treat
Anaerobic infections below the diaphragm
Clinical uses of Metronidazole
- Entamoeba histolytica
- Giardia
- Trichomonas (vaginitis and cervicitis)
- Gardnerella vaginalis
- H. Pylori (can substitute for Amoxicillin if allergic)
- C. Diff
Define Toxic epidermal necrolysis
Same as SJS but involving >30% of body (whereas SJS <10%)
Common drug causes of SJS
- Seizure medications (Ethosuximide, Carbamazepine, Lamotrigine, Phenytoin, Phenobarbitol)
- Sulfa medication
- Penicillin
- Allopurinol
Tx of SJS
o Supportive care ♣ IV fluids ♣ Watch airway ♣ Skin for superinfection ♣ Ophthalmologic referral in EVERY patient
What is Brudzinski sign
A physical finding consistent with meningitis; while the pt is supine, the neck is passively flexed resulting in involuntary knee and hip flexion
What is Kernig sign
A physical finding consistent with meningitis; while the pt is supine, the legs are flexed at the kip and knee at 90 degree angle resulting in pain with leg extension
Empiric tx of meningitis in neonate
Think about GBS, E. Coli, and Listeria
Ampicillin + Ceftriaxone
What bacteria is even more likely to cause meningitis in a sickle cell patient
Strep pneumo
Sickle cell = functional asplenia = susceptible to encapsulated organisms
Define dysentery
• Intestinal infection resulting in severe bloody diarrhea with mucus
Define enteritis
• Inflammation of the small intestine, usually resulting in diarrhea; may be because of infection, immune response, or other causes
Most common causes of bacterial diarrhea
Salmonella, Shigella, Campylobacter
Tx of hemolytic uremic syndrome
Mostly supportive = fluid and electrolytes
Early dialysis may be needed
Tx of Salmonella dysentery
Fluid and electrolyte correction
Abx do not shorten GI course and may increase risk of HUS
Tx of Shigella dysentery
Is self-limited by often treated with abx because they can shorten the course and decrease shedding
Are seizures more common with epidural or subdural hematomas
Subdural
What bug is common cause of UTI in sexually active females
Staph saprophyticus
Which staph is coag positive vs. coag negative
- Staph aureus = coag positive
- Staph epi and sapro = coag negative
What are the 3 main symptoms of scarlet fever
1) Redness and swelling of tongue
2) Pharyngitis
3) Rash that spares the face
What are the symptoms of Rheumatic fever
♣ J – joints – poly arthritis
♣ O – in the shape of a heart – valvular damage, myocarditis, and pericarditis
♣ N – subcutaneous nodules – usually on extensor surfaces
♣ E – erythema marginatum – rash with thick red borders
♣ S – Sydenhams’ chorea – rapid involuntary movements, especially of hands and face
Describe pathogenesis of rheumatic fever
Type II HSR - antibodies against M protein will have molecular mimicry with myocin in the heart
What diseases may precede RF vs. PSGN
- RF only after pharyngitis
- PSGN after pharyngitis or superficial infection (e.g. impetigo)
How does early tx of strep pharyngitis affect risk of RF vs. PSGN
Early tx of strep will prevent RF but not PGSN
So RF is better off in both cases - only occurs after a single disease and can be prevented if that disease is treated
Common diseases of strep pneumo
MOPS: M = meningitis O = otitis media P = pneumonia S = sinusitis
Common diseases of Enterococcus
do U Heart Trees:
- U = UTI
- Heart = endocarditis
- Trees = biliary tree infections
Tx of Enterococcus
Linezolid, Daptomycin, Tigecycline
Describe Type 1 RTA
♣ Distal renal tubular acidosis -> defect in collecting tubule (decreased secretion of H+)
♣ Alpha-intercalated cells are unable to secrete H+ -> acidosis
♣ Hypokalemia
♣ Urine pH will be > 5.5 (because no H+ in urine)
Describe Type 2 RTA
♣ Proximal renal tubular acidosis -> defect in proximal tubule
♣ Impaired HCO3- reabsorption -> Increased HCO3- excretion -> acidosis
♣ Hypokalemia and hypophosphatemia
♣ Urine pH < 5.5 (urine is acidified by a-intercalated cells in collecting tubule)
Describe Type 4 RTA
♣ Hyperkalemic renal tubular acidosis
♣ Due to hypoaldosteronism -> decreased K+ secretion -> hyperkalemia
♣ Hyperkalemia prevents collecting tubules from generating NH4+ -> impaired ammonium excretion
♣ Urine pH < 5.5 (decreased aldosterone = decreased Na+ reabsorption = increased Na+ in lumen = positively charged lumen)
Diagnose: bone pain that worsens at night, resolves with NSAIDs, imaging reveals bone mass with radiolucent core
Osteoid osteoma
When should immunizations be given to premature babies - at chronological age, or at gestational age
Chronologic age
What will you see on lateral XR in epiglottis
“thumb sign” = swollen epiglottis
What will you see on lateral XR in retropharyngeal abscess
Widened prevertebral space
What bone tumors occur at the epiphysis
Giant cell (soap bubble appearance)
What bone tumors occur at the metaphysis
Osteochondroma, osteosarcoma
What bone tumors occur at the diaphysis
Ewing sarcoma, Osteoid osteoma, Myeloma
What will you see on XR in Osteosarcoma
♣ Imaging reveals a mass with sunburst appearance and lifting of periosteum (Codman triangle)
• THINK: osteoSarComa (S = sunburst and C = Codman)
What will you see on XR in Ewing sarcoma
♣ X-ray reveals “onion-skin” appearance – tumor grows within medullary center of bone, pushing outwards and causing periosteum (outer layer) to lay down new layers of bone
THINK: eWING = Chicken WINGS and onion rings
Describe Wiskott-Aldrich Syndrome
o X-linked recessive immunodeficiency due to mutation in WASp gene
o Leukocytes and platelets unable to reorganize actin skeleton defective antigen presentation
o WATER - Wiskott Aldrich, microThrombocytopenia, Eczema (especially truncal), Recurrent infections
o Treatment – stem cell transplant
