1. Background

Ear nose and throat (ENT) infections are common clinical problems occurring in the general population and are a cause of serious morbidity and debility. These infections affects the normal daily functioning of both adults and children and are the frequent cause of absenteeism from work and school among school aged children[1]. As with other infections of the upper respiratory tract (URT), ear infections such as chronic suppurative otitis media are of great concern especially in developing countries, such as retarded language development and progress in school among children[2, 3]. Otitis-media (which means an inflammation and infection of the middle ear) is now known to be the most common childhood infection which leads annually to the death of over 50,000 children under 5 years[4].

The prevalence rate of ENT diseases is particularly high in developing countries; diseases such as Otitis media had a reported prevalence of 65%[5]. The WHO estimated that URT infections generated a 94.6% disability adjusted life years and were responsible for 6.9% of the global number of deaths in 2002[6]. Otitis media infection occurs less common in adults compared to children, it is one of the most common reasons parents take their children to the hospital. According to a report[7, 8] acute otitis media are the most common childhood infection and the most common indication for antibiotic use in children. In the USA acute otitis media is responsible for up to 20 million physician visit per year representing an average of 2.9 physician office visits per child[9].

One of the ENT diseases resistant to current antibiotics is chronic suppurative otitis media (CSOM)[10].Chronic suppurative otitis media is an infection of the middle ear lasting for more than two weeks, mostly (CSOM) holds perforation of the tympanic membrane and discharging [11] for at least two weeks. Many factors predisposes individuals to CSOM, they include genetic, infectious, hygienic and environmental factors[12]. Other less common causes includes low socio-economic status, allergy and overcrowding[12]. The major complication of CSOM is hearing impairment which may be preceded by purulent otitis often with perforation and further complications including recurrent acute otitis media, persistence of middle ear effusion which requires the insertion of drainage tube, mastoiditis, meningitis, brain abscess and sepsis[13].

Different group of drugs are employed in the management of ear infection; such drugs include analgesics, anti histamines, antiallergins and antibiotics. The drugs are administered in the form of tablets, capsules, syrups and instillations. Antibiotics appear to be the most frequently used class of drugs owing to the etiology of the disease condition. The prescription and use of antibiotics in URT infections as with other infections is facing a lot of challenges which include over use and misuse which leads to development of resistance[14]. Variability in the prescription of antibiotics do occur and this can be attributed to the infecting organism and antimicrobial susceptibility that differs from country to country, other factors may include physician preference, local policy, costs and lack of local guidelines[15].

The present study explored the pattern of prescription of drugs used for the treatment of chronic suppurative otitis media in a Tertiary Ear Care centre in Kaduna Nigeria. The study is aimed at critically analyzing the prescriptions issued from the outpatient department of the hospital. It is the desire of the study to find out areas that needs adjustment and improvement in the overall interest of the patient and the healthcare system.

2. Materials and Methods

2.1. Setting

The study was carried out in the out- patient department of the National Ear Care Centre Kaduna, Nigeria between January and May 2011 (six months).

2.2. Study Design

It was a cross sectional retrospective study and was based on the prescriptions coming to the pharmacy from the outpatient clinic of the Hospital.

2.3. Study Population

The present study was conducted on 121 prescriptions which were obtained from the prescription records of the pharmacy Department of the Hospital. Seventy one Prescriptions were found to satisfy the inclusion criteria for the study. The sample prescriptions were investigated using a checklist for the following items: Legibility of handwriting, date of prescription, patient’s name in full, patient’s address, patient’s age, patient’s sex, doctor’s name, doctor’s signature in ink, dosage form, type and number of drugs prescribed and the number of drugs per prescription. Other Information obtained from the patient case files were the presenting symptoms and the diagnosis. The study population included all patients whose prescription was filled at the pharmacy those patients that did not obtain their drugs from the pharmacy were not included.

2.4. Parameters for Evaluation

The WHO/INRUD methods of describing core prescribing indicators were employed. The average number of medicines per prescription was calculated by dividing the total number of drugs by the number of encounters. Percentage encounter with generic name, percentage encounter with antibiotics and percentage encounter with injections were determined by dividing the number of occurrence by the total number of event, respectively and multiplying by 100. Other parameters evaluated includes gender distribution, average age range of patients, types of infections, most commonly used agents of a particular class, comparison of antibacterial prescribed in monotherapy versus fixed dose combination therapy and mode of administration.

3. Results

During the study period (Jan- May, 2011) a total of 71 prescriptions were evaluated. Out of the total number of patients, 41 patients were males and 30 females. Among total patients 46 were children (1-12years) and 25 adults (>13 years). During the study it was observed that the highest number of patients was in the age group (1-10 years) and the geriatric group was the least [Table 1]. The major presenting complain was ear discharge 76.5%, followed by hearing loss and otorrhea 8.8% [Table 2].

Table 1. Age distribution

Table 2. Diagnostic symptoms

A total of 548 drugs were prescribed for CSOM patients, Antibiotics were the most prescribed (48%), followed by antihistamines 21.5% and then multivitamins 15% [Table 3].

Table 3. Type of drugs prescribed for CSOM Class of drug Frequency of prescription Percentage % Antibiotics 263 48.0 Analgesics 15 2.7 Antihistamines 118 21.5 Steroids 6 1.1 Antibiotics + Steroids 14 2.6 Multivitamins 82 15.0 Miscellaneous 50548 9.1100

A total of 263 antibiotics were prescribed. Quinolones were the most prescribed 44.5%, followed by pennicillins 31.6%, nitroimidazoles 13.7%, cephalosporins 6.8%, aminoglycoside 1.9% and macrolides 1.5% [Table 4]. The most commonly used agent among the quinolones was ofloxacin, among the pennicillins augmentin was the most prescribed. The nitroimidazole, metronidazole was also significantly prescribed 13.7%.

Table 4. Most commonly used antibiotic

A total of 548 drugs were prescribed in the prescriptions investigated. The routes of administration were oral 425 (78.4%), intravenous 41 (7.6%) and ear drops 82 (14%). The average number of medicine per prescription is 7.7, the range being 1-11[16].

Table 5. WHO/INRUD core prescribing indicators

4. Discussion

This study comprises essentially of an audit of various prescriptions issued for the treatment of chronic suppurative otitis media carried out over a period of six months (January- may 2011). Data collected from 71 prescriptions were analysed, and the findings compared with similar studies published. The study targeted chronic suppurative otitis media alone, therefore, prescriptions for acute otitis media and other ENT diseases were excluded.

Demographic data showed that 60.6% of the patients were children between the ages of (1-10 years). These finding are consistent with 34-46 % reported in previous studies[17, 18]. Anatomical and immunological considerations could be the reason why children are more susceptible to this infection; the Eustachian tube in children is shorter and more horizontal than adults and is made up of more flacid cartillage which can impair its opening[19]. Another point for consideration is the immature nature of children’s immunity[20]. The study also showed that the percentage of males suffering from CSOM was more than females. Similar findings were reported by[21, 22].

Ear discharge (otorrhea) was the most common diagnostic symptom in 85.3%, followed by hearing loss 8.8%. Nasal discharge, cough and swelling were the least observed diagnostic symptoms 1.5% respectively. Similar result of 50% presentation of otorrhea was reported by[23] in a study of the prevalence of chronic suppurative otitis media and hearing impairment in Basrah city, the result disagreed with the result of[24] who reported that otorrhea was commonly found in otitis externa. Hearing loss was present in 8.8% of the patients, this was significantly lower than a presentation of 55.5% as reported by[23]. The specificity of the researched disease condition (CSOM) accounts for the low value of the other diagnostic symptoms in (table 2).

Antibiotics were the most prescribed drugs in this study (48%), followed by antihistamines 21.5% and multivitamins 15%. Another class are the miscellaneous groups (9.1%), such as ear drops, oils such as eucalyptus oil, nasal drops and nasal spray. Analgesic and steroids were the least prescribed. Previous study of the prescription pattern of CSOM also indicated a prevalent prescription of antibiotics such as[25] and[26].

Most commonly prescribed class of antibiotics were the quinolones (44.5%), closely followed by the Pennicillins (25.1%) and the Nitroimidazoles 13.7%.The cephalosporins frequency was 6.8%, followed by the Aminoglycosides 1.9% and the least prescribed was the macrolides 1.5%. Most studies favour the use of the Pennicillins and cephalosporins over the quinolones[25, 26]. The preference for quinolones was observed in some past studies as was the case with this study, this could be due to the fact that the drugs have oral antipseudomonal activity and lack ototoxicity side effect[27]. The oral and topical quinolones have been used effectively in children and such use will avert the inconveniences of the parentheral antibiotics[28,29,30].

Most of the drugs in the study were prescribed using brand names (data not displayed) and the average number of medicine per prescription was 7.6, the range being (1-11) [16]. Orally administered drugs were the most frequent dosage forms in this study (78.4%), this could be due to convenience especially in children.

5. Conclusions

The prescription behaviour of physician in the hospital under review is encouraging. The report is in line with results obtained from similar studies; however there is a need to improve on the use of generic names instead of brand names and the need to use less number of drugs per patient.

ACKNOWLEDGEMENTS

The authors wish to express their appreciation to the management of the National ear care centre Kaduna, Nigeria for providing the enabled environment that made this research successful.