1. Causes of sinus congestion
-Chronic sinusitis (mucosal thickening) 2/2 chronic infection or inflammation
-Allergic rhinitis
-Physical obstruction (polyps, inverted papilloma, severe deviated septum, large adenoids)
2. Copious, clear rhinorrhea-- if it drips like a faucet, is in an old person, tastes salty, and worsens when the person leans forward, worry about CSF leak. It can occur with pituitary lesion or spontaneously.
3. Gut microbiome can influence generation of toxic metabolites in people taking tylenol: Pharmacometabonomic identification of a significant host-microbiome metabolic interaction affecting human drug metabolism. {PNAS, 2009} "....in individuals with high bacterially mediated p-cresol generation, competitive O-sulfonation of p-cresol reduces the effective systemic capacity to sulfonate acetaminophen..."
4. Gut microbiome influences behavior; transfer of gut microbiome = transfer of behavioral preferences. "Commensal bacteria play a role in mating preference of Drosophila melanogaster" {PNAS 2010} "...In this study, mating preference was achieved by dividing a population of Drosophila melanogaster and rearing one part on a molasses medium and the other on a starch medium. When the isolated populations were mixed, “molasses flies” preferred to mate with other molasses flies and “starch flies” preferred to mate with other starch flies.... Antibiotic treatment abolished mating preference, suggesting that the fly microbiota was responsible for the phenomenon. This was confirmed by infection experiments with microbiota obtained from the fly media (before antibiotic treatment) as well as with a mixed culture of Lactobacillus species and a pure culture of Lactobacillus plantarum isolated from starch flies. Analytical data suggest that symbiotic bacteria can influence mating preference by changing the levels of cuticular hydrocarbon sex pheromones...."
5. Nosebleeds in...
-Children, are generally benign, as they are due to superficial vessel rupture in the anterior septum. Holding pressure makes them stop in a few minutes, they rarely lose enough to lead to anemia. Manage preventatively-- they are worse with dryness, so keep it locally moist by using topical vaseline and saline drops multiple times a day. Humidifier in the room is not super helpful, but can be used. If it's not able to be controlled this way, you can cauterize. If you're worried about a bleeding diathesis, ask them if they bled a lot when they lost their baby teeth, or if they've had surgery ask about bleeding during surgery; if that was normal, bleeding diathesis is unlikely.
-Teenagers, think angiofibromas
-Adults, are often quite serious. They are usually posterior nasal bleeds from the sphenopalatine artery, and are due to vascular pathology (arterioloscelerosis + hypertension -> rupture). They can lose a LOT of blood, and you can't hold pressure because they are posterior, under the nasal bones. Sometimes they will require IR embolization of the sphenopalatine artery.
6. Hearing test: Otoacoustic emissions
-This is the newborn hearing screen.
-"An otoacoustic emission (OAE) is a sound which is generated from within the inner ear....OAEs are considered to be related to the amplification function of the cochlea. In the absence of external stimulation, the activity of the cochlear amplifier increases, leading to the production of sound. Several lines of evidence suggest that, in mammals, outer hair cells are the elements that enhance cochlear sensitivity and frequency selectivity and hence act as the energy sources for amplification. One theory is that they act to increase the discriminability of signal variations in continuous noise by lowering the masking effect of its cochlear amplification.... Studies have shown that OAEs disappear after the inner ear has been damaged, so OAEs are often used in the laboratory and the clinic as a measure of inner ear health." (wikipedia)
-Evoked OAE: "Stimulus Frequency OAEs (SFOAEs) are measured during the application of a pure-tone stimulus, and are detected by the vectorial difference between the stimulus waveform and the recorded waveform (which consists of the sum of the stimulus and the OAE). Transient-evoked OAEs (TEOAEs or TrOAEs) are evoked using a click (broad frequency range) or toneburst (brief duration pure tone) stimulus. The evoked response from a click covers the frequency range up to around 4 kHz, while a toneburst will elicit a response from the region that has the same frequency as the pure tone." (wikipedia)
-Put a probe in the ear, play a sound, the probe records a response
-Benefits: fast, doesn't require sedation, only that they sit still/quiet for a few minutes, doesn't depend on behavioral response from child,
-Cons: you only get a yes/no response, no quantitative outcomes, any pathology in the ear (fluid in drum, eustachian tube pathology) will throw off the readings as you will not be able to record the OAE.
7. Hearing test: Auditory brainstem response (ABR)
"The ABR is an auditory evoked potential extracted from ongoing electrical activity in the brain and recorded via electrodes placed on the scalp. The resulting recording is a series of vertex positive waves of which I through V are evaluated.... The following are believed to be the sources of the waves:
Wave I – generated by cranial nerve VIII
Wave II – generated by the cochlear nucleus
Wave III – generated by the superior olivary complex
Wave IV – generated by the lateral lemniscus
Wave V – generated by the inferior colliculus"
(from wikipedia)
-You play a sound (start at 90 dB, gradually lower to see when the responses stop coming-- if you still see wave V at 20 dB that's a normal test) and then record the response with electrodes over the scalp. You can play clicks at different frequencies to find out about hearing loss at different frequencies.
-Pros: you get quantitative results, you can check responses at different frequencies, it's detailed data
-Cons: Child needs to be sedated for ~30-40 minutes
8. Hearing test: sound field
-Put the kid in a box, play sounds, look at their behavior/response to see if they hear the sound.
-Pros: non invasive, no sedation, fast, cheap
-Cons: not ear-specific (if one ear is bad, the other can obviously compensate), requires cooperation of child-- usually the child needs to be older than 6-9 mos for this test, any younger and you can't get good data from it.
-This is not really meant to stand alone, it's usually a clinical correlate to the ABR
9. Hearing/ear test: tympanometry 
-Apply pressure (from -200 to +200 mmH20) in ear, and then measure the compliance of the ear drum by emitting a pure tone and measuring how much is reflected.
-Normally the peak of mobility will be in the center of pressure (at 0 mmH20, neutral)
-If the ear is heavily retracted (usu eustachian tube dysfunctio) the peak of mobility will be at negative intracanal pressure-- as pulling the TM closer to neutral makes it work better.
-A flat tympanogram means the drum is not moving and something is wrong
10. Thyroglossal duct cyst: 
-A midline neck mass in a child is a thyroglossal duct cyst (TDC) until otherwise proven (off to the side usually lymph nodes, but rarely TDC can appear off midline.
-Before you surgically remove it, get an ultrasound to make sure they have a normal thyroid gland, as some people's only thyroid tissues is in the TDC. The u/s also looks at the anatomy of the TDC.
-Usually infrahyoid
-Treatment is surgical removal, and you don't just want to scoop out the cyst as the rate of recurrence is 25%. You want to remove the entire tract of the thyroglossal duct up to tongue, including removing the central part of the hyoid bone. The recurrence after this surgery is much lower