Post-tympanostomy tube otorrhea.
Post-tympanostomy tube otorrhea is a common problem that is treated by both primary care physicians and otolaryngologists. Physicians should take a logical approach to managing this condition in order to prevent the development of antimicrobial resistance and to minimize healthcare expenditures. Once the diagnosis has been made, first-line therapy with fluoroquinolone drops, with or without suctioning, is preferred. If the condition does not resolve after a few days, suctioning is recommended and oral antimicrobial therapy can be initiated, depending on the clinical situation. Parenteral therapy is sometimes necessary for those very few patients who do not improve with oral and topical antimicrobial therapy and aggressive local care. The use of prophylactic drug therapy is controversial.
Post-tympanostomy tube otorrhea (PTTO) is a relatively common condition seen by physicians who care for children. It is estimated that approximately 500,000 to 2 million ventilating tubes are placed on an annual basis in the United States.  Gross et al reported that at a minimum, between 10 and 29% of tubes will drain sometime after they have been placed.  Other reports have placed this figure as high as 74% [2,3]
Although PTTO is not serious in most cases, almost all patients experience some degree of hearing loss and discomfort. In this era of increasing antimicrobial resistance and in view of the current challenges with respect to healthcare economics, the development of a cost-effective treatment program that would quickly control otorrhea while minimizing the risk of bacterial resistance is essential.
Obviously, the first step to achieving both financial and physiologic well-being is to quickly recognize otitis media when it occurs following ventilating tube placement. The presence of acute otitis media without otorrhea in a child with patent ventilating tubes is exceptionally uncommon. One of the most frustrating situations that clinicians face is in trying to evaluate a patient with a history of recurrent acute otitis media following tympanostomy tube placement when the patient has never had otorrhea.
Clinical characteristics of PTTO
Several clinical stages of PTTO have been described, although the cutoff points are somewhat arbitrary.  Drainage that occurs within the first 2 weeks following tube placement is categorized as early PTTO. Late PTTO occurs at least 2 weeks following placement. Should the drainage persist for more than 8 weeks, the problem is classified as chronic PTTO. This 8-week cutoff point is widely accepted in the literature, but it is an arbitrary figure that has no basis in actual scientific fact.  In fact, in light of the increase in antimicrobial resistance, many clinicians would not wait 8 weeks to obtain cultures in order to guide drug therapy. Rather, cultures might be obtained within just a few weeks of the onset of drainage, because parenteral therapy might be required to treat opportunistic organisms. Therefore, we might see a change in the definition of chronic PTTO in time.
PTTO is also classified as either simple or complicated. Patients with simple PTTO generally experience painless otorrhea that is not accompanied by any associated upper respiratory tract infection or other systemic disease. Therapy can be directed solely at acute otitis media. Children with complicated PTTO have either an associated upper respiratory tract infection, periauricular cellulitis, or occlusion of the external auditory canal. These concomitant conditions might prevent the successful administration of ototopical antimicrobial therapy unless a wick is placed. In these patients, systemic antimicrobial therapy is frequently recommended in addition to ototopical medication.
The pathogenic etiology of PTTO is associated with several factors, including the onset of drainage, previous exposure to antimicrobial therapy, and the patient's age. In addition, the physician must remember that the organisms that are typically associated with acute otitis media (Streptococcus pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis) are more common during the winter months. In contrast, Pseudomonas aeruginosa and Staphylococcus spp. are more common during the swimming season.
Onset. Drainage that occurs within 2 weeks of tube placement is usually the result of either an infection that had already existed when the tube was placed or contamination of the external auditory canal during the operation. PTTO that arises after 2 weeks or so is most likely the result of either water contamination or an upper respiratory tract infection (the latter is sometimes accompanied by nasopharyngeal reflux). Drainage that has been present for more than several weeks following tube placement is most likely associated with the development of an opportunistic infection by anaerobes, yeast, staphylococci, or P aeruginosa.
Previous antibiotic use. The presence of a resistant organism is more common in children who have already received multiple courses of antibiotics than it is in those who have not. The chronic use of ototopical therapy might be associated with the appearance of yeast in the external auditory canal. Obtaining a PTTO culture is especially valuable in patients who have had multiple exposures to systemic or topical antibiotics.
Age. In children younger than 3 years of age, PTTO organisms are usually the same as those seen in acute otitis media, particularly S pnewnoniae and H influenzae, although Staphylococcus epidermidis and P aeruginosa are not uncommon. Children older than 3 years of age are more likely to harbor organisms that often arise from water exposure, including Staphylococcus aureus, S epidermidis, and P aeruginosa. [6-8]
Although the data are inconclusive, there is probably no prophylactic benefit to sterilizing the external auditory canal prior to placing a ventilating tube. [2,9] Once a tube has been placed, either oral or topical prophylaxis might play some role in preventing early PTTO, but neither alternative has been studied extensively, and those conclusions that have been drawn are not particularly convincing.
Oral agents. An otolaryngologist who chooses to administer oral prophylaxis must keep in mind that most patients have already been on an antibiotic immediately prior to tube placement; also, compliance might be a problem. Clinicians must also examine the cost-effectiveness of such a preventive plan. There are no good guidelines available to help the physician select a particular oral drug regimen.
Topical agents. Not much clearer is the role of topical antimicrobial prophylaxis. There is no clear consensus as to which drug to use, when to use it (intraoperatively, postoperatively, or both), and how long to use it. Some clinicians base their prophylaxis decisions on the likelihood that drainage will occur, although there is controversy over this issue as well. Some reports indicate that a number of factors have no effect on the rate of early PTTO: previous tympanostomy tube placement, a dry ear or serous effusion at the time of placement, the use of a silver-oxide-impregnated tube, and a concurrent tonsillectomy, adenoidectomy, or adenotonsillectomy. [2-4,10,11] Other factors have been implicated as possibly increasing the risk of early PTTO: a preoperative diagnosis of recurrent acute otitis media, a mucoid or purulent effusion or a positive culture at the time of placement, young age (because of an immature immune function and/or increased viral exposures), male sex, the use of a large-bore tympanosto my tube, and bleeding at the myringotomy site. [9,10,12-14]
Specific prophylactic and therapeutic modalities
Because it is difficult to administer otic drops to some children, it would be ideal if we had an oral prophylactic agent that covered a broad antimicrobial spectrum (including P aeruginosa) and that was approved for children. Unfortunately, the reality is that the best oral option we have--the fluoroquinolones--are not approved for children. These drugs are also associated with possible complications (e.g., altered bone growth), and they are the subject of significant concerns over the development of resistance. We do have parenteral alternatives, but concerns over their expense and potential ototoxicity make this option unrealistic. Therefore, we are left with ototopical therapy as the best option for both prophylaxis and treatment of otorrhea in the immediate postoperative period. [15,16]
Intraoperative saline irrigation. One alternative to postoperative prophylactic antibiotic drops is saline irrigation in the operating room. Gross et al demonstrated that this therapy is effective, and it has several advantages over prophylactic antimicrobial drops.  For example, intraoperative saline irrigation might lower the risk that a patient will develop sensorineural hearing loss, ototoxicity, and dermatitis, and it is less expensive than antimicrobial drops. It also avoids problems associated with the administration of drops and with antibiotic resistance.
There are no standards regarding the timing or duration of antimicrobial-drop therapy following tube placement. Advocates of intraoperative use have recommended two strategies: filling the middle ear during tube placement and filling the external auditory canal following placement.  Physicians who choose to use antimicrobial drops following surgery must decide whether to administer a single application or multiple doses, which usually continue for as long as 3 to 5 days. [1-4,10-12,16]
Sulfacetamide drops. Sulfacetamide drops are bacteriostatic against H influenzae, M catarrhalis, and most pneumococci, which are common organisms seen in acute otitis media and chronic otitis media with effusion. This agent is not effective against S aureus and P aeruginosa, common organisms that are found in chronic suppurative otitis media, acute otitis externa, and infected surgical wounds. Therefore, sulfacetamide is initially very cost-effective as a treatment for PTTO, but it might not be the drug of choice later on in patients who have intermittent or refractory otorrhea.
Neomycin/polymyxin B drops. The fixed-combination agent neomycin/polymyxin B is bacteriocidal against P aeruginosa, Staphylococcus spp., and most of the gramnegative organisms that are seen in chronic suppurative otitis media. However, it is not effective against Bacteroides fragilis, streptococci, and pneumococci, which are some of the more common organisms found in both acute otitis media and chronic otitis media with effusion. The use of neomycin/polymyxin B in an ear that has a patent ventilating tube or a perforation is also of concern because of the potential for ototoxicity.  Contact dermatitis can also be problematic.
Fluoroquinolone drops. Unlike sulfacetamide and neomycin/polymyxin B drops, fluoroquinolone drops (ciprofloxacin and ofloxacin) cover a broad bacterial spectrum, including those organisms that are associated with acute otitis media, chronic otitis media with effusion, chronic suppurative otitis media, and acute otitis extema. They also pose no known risk of ototoxicity, and they can be very cost-effective in patients who have repeated episodes of PTTO.
The topical fluoroquinolones kill bacteria in vitro in a concentration-dependent manner. Local administration at a high concentration (3 [micro]g/ml) will cause a rapid decrease in the density of the bacteria. Topical fluoroquinolones carry a markedly lower risk of resistance than do oral fluoroquinolones, which can be administered in concentrations of only 1 to 5 [micro]g/ml. [15,17-20] On occasion, the prolonged use of topical (and occasionally systemic) antibiotics will lead to the growth of' yeast in the extemal auditory canal. Such an infection usually responds to clotrimazole, although prolonged ketoconazole is sometimes necessary. 
Amoxicillin/clavulanate. In addition to monotherapy with antimicrobial drops and combination therapy with topical and oral antimicrobials, fixed-combination amoxicillin/clavulanate, with or without prednisolone, has been studied for the treatment of acute PTTO. Ruohola et al found that the addition of the steroid provided a modest advantage over antimicrobial therapy alone. 
In theory, the treatment of PTTO is a laborious and time-consuming process. Each child must be suctioned, and a culture sample must be obtained. Depending on culture results and the presence or absence of an associated respiratory illness, each patient must undergo ototopical and/or systemic therapy. Each must return at regular intervals for additional suctioning as necessary. Once the otorrhea has resolved, the physician must decide whether to initiate prophylactic antimicrobial therapy (although such therapy is undertaken much less often now in light of the risk of resistance). Physicians who do opt to administer prophylaxis for patients with respiratory infections might find that pulsed therapy is more appropriate than continuous therapy.
In reality, physicians frequently initiate topical therapy after receiving a telephone call from a parent whose child has just begun experiencing PTTO. Oral antimicrobial treatment is started when a patient has signs and symptoms of an associated rhinosinusitis. If the patient does not improve rapidly, an office evaluation and suctioning are often necessary. Again, the patient must return at regular intervals for repeat suctioning as necessary, and in selected cases, the physician can start prophylaxis after the infection has resolved.
From the Department of Pediatric Otolaryngology, Children's Hospital Medical Center, Cincinnati.
Adapted from an educational seminar sponsored by Alcon Laboratories and presented during the annual meeting of the American Academy of Otolaryngology-Head and Neck Surgery, Washington, D.C., Sept. 26, 2000.
(1.) Gross RD, Burgess LP, Holtel MR, et al. Saline irrigation in the prevention of otorrhea after tympanostomy tube placement. Laryngoscope 2000;110:246-9.
(2.) Gates GA, Avery C, Prihoda TJ, Holt GR. Post-tympanostomy otorrhea. Laryngoscope 1986;96:630-4.
(3.) Charnock DR. Early postoperative otorrhea after tympanostomy tube placement: A comparison of topical ophthalmic and otic drops. Ear Nose Throat J 1997;76:870-1.
(4.) Golz A, Ghersin T, Joachims HZ, et al. Prophylactic treatment after ventilation tube insertion: Comparison of various methods. Otolaryngol Head Neck Surg 1995;119:117-20.
(5.) Kenna MA, Bluestone CD, Reilly JS, Lusk RP. Medical management of chronic suppurative otitis media without cholesteatoma in children. Laryngoscope 1956;96: 146-51.
(6.) Schneider ML. Bacteriology of otorrhea from tympanostomy tubes. Arch Otolaryngol Head Neck Surg 1959;115:1225-6.
(7.) Mandel EM, Casselbrant ML, Kurs-Lasky M. Acute otorrhea: Bacteriology of a common complication of tympanostomy tubes. Ann Otol Rhinol Laryngol 1994;103:713-8.
(8.) Brook I, Yocum P, Shah K. Aerobic and anaerobic bacteriology of otorrhea associated with tympanostomy tubes in children. Acta Otolaryngol 1998;118:206-10.
(9.) Baldwin RL, Aland J. The effects of povidone-iodine preparation on the incidence of post-tympanostomy otorthen. Otolaryngol Head Neck Surg 1990;102:631-4.
(10.) Hester TO, Jones RO, Archer SM, Haydon RC. Prophylactic antibiotic drops after tympanostomy tube placement. Arch Otolaryngol Head Neck Surg 1995;121:445-8.
(11.) Scott BA, Strunk CL Jr. Post-tympanostomy otorrhea: A randomized clinical trial of topical prophylaxis. Otolaryngol Head Neck Surg 1992;106:34-41.
(12.) Valtonen H, Qvarnberg Y, Puhakka H, Nuutinen J. Early posttympanoslomy otorrhea in children under 17 months of age. Acta Otolaryngol 1997;117:569-73.
(13.) Chole RA, Hubbell RN. Antimicrobial activity of silastic tympanostomy tubes impregnated with silver oxide: A double-blind randomized multicenter trial. Arch Otolaryngol Head Neck Surg 1995;121:562-5.
(14.) Gourin CG, Hubbell RN. Otorrhea after insertion of silver oxide-impregnated silastic tympanostomy tubes. Arch Otolaryngol Head Neck Surg 1999;125:446-50.
(15.) Esposito S. D'Errico G, Montanaro C. Topical and oral treatment of chronic otitis media with ciprofloxacin. A preliminary study. Arch Otolaryngol Head Neck Surg 1990; 116:557-9.
(16.) Zipfel TE, Wood WE, Street DF, et al. The effect of topical ciprofloxacin on postoperative otorrhea after tympanostomy tube insertion. Am J Otol 1999;20:416-20.
(17.) Pickett BP, Shinn JB, Smith MF. Ear drop ototoxicity: Reality or myth? Am J Otol 1997;18:782-9.
(18.) Dohar JE, Garner ET, Nielsen RW, et al. Topical ofloxacin treatment of otorrhea in children with tympanostomy tubes. Arch Otolaryngol Head Neck Surg 1999;125:537-45.
(19.) Wintermeyer SM, Hart MC, Nahata MC. Efficacy of ototopical ciprofloxacin in pediatric patients with otorrhea. Otolaryngol Head Neck Surg 1997;116:450-3.
(20.) Force RW, Hart MC, Plummer SA, et al. Topical ciprofloxacin for otorrhea after tympanostomy tube placement. Arch Otolaryngol Head Neck Surg 1995;121:880-4.
(21.) Tom LW. Ototoxicity of common topical antimycotic preparations. Laryngoscope 2000;110:509-16.
(22.) Ruohola A, Heikkinen T, Jero J, et al. Oral prednisolone is an effective adjuvant therapy for acute otitis media with discharge through tympanostomy tubes. J Pediatr 1999;134:459-63.