Introduction
Otitis media comprises inflammation of the middle-ear cleft. It remains a relevant topic of research both in the developing and the developed world. It is the most common otological presentation in most ENT unitsReference Okafor1 and is commonly encountered in general practice.Reference Lasisi, Fawole, Usman and Sobode2 The anatomical relation between the small middle-ear cleft in the temporal bone and the middle cranial fossa superiorly makes spreading infection in this space potentially fatal.Reference Mawson and Ludman3 However, the incidences of this and other forms of complications have reduced tremendously since the advent of antibiotics.
However, within rural and some semi-urban communities in developing countries such as Nigeria, the interplay of poverty and inadequate specialist ENT health care still makes complications of chronic suppurative otitis media (CSOM) a problem for the few available otolaryngologists. Late presentation and low socioeconomic factors are identifiable risk factors for the development of such complications.
This study assessed CSOM amongst patients presenting at the otorhinolaryngology unit of Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria, with a view to determining its prevalence and identifying associated complications. We also discuss the problems we encountered in managing these cases.
Method
The study was prospectively carried out in a teaching hospital in south-western Nigeria.
We included 160 consecutive patients presenting at our hospital for the first time with symptoms and signs of CSOM, between January 2004 and December 2005. Data were collected using a questionnaire. This was administered to the patient or their parent by the interviewer (one of the authors) in order to obtain demographic information and a history of the disease, its predisposing factors and associated complications.
Each of the patients was fully examined and underwent otoscopy. Hearing was clinically tested using tuning forks (i.e. Rhinnes and Weber tests), and pure tone audiometry was performed for patients requiring further audiological evaluation. An X-ray of the mastoids and a computed tomography (CT) scan were performed as appropriate.
Data were recorded and analysed using the Statistical Package for the Social Sciences software version 11 (SPSS Inc, Chicago, Illinois, USA). Results are presented using descriptive statistics and percentages.
Results
A total of 1441 new patients were seen at our hospital between January 2004 and December 2005. Of these, 746 were otological cases, of which 160 were CSOM. Acute otitis media was seen in 51 patients, while otitis media with effusion was seen in 54 patients.
Age distribution
Forty-eight (30 per cent) of the 160 patients with CSOM were aged between zero and five years, while 21 (13.1 per cent) were aged between six and 10 years. Another 14 (8.6 per cent) were aged between 11 and 15 years. This shows that about half of the patients seen were younger children. Adolescents (16–20 years) and young adults (21–30 years) constituted 11.3 and 19.4 per cent of the patients, respectively (Table I).
Age distribution of patients presenting with CSOM
CSOM = chronic suppurative otitis media
Sex distribution
There were 87 males (54.4 per cent) and 73 females (45.6 per cent), giving a male to female ratio of 1:1.
Place of domicile
Sixty-seven (41.9 per cent) of the patients were from rural areas, 44 (27.5 per cent) were from semi-urban areas and 49 (30.6 per cent) were from urban areas.
Laterality
One hundred and eight of the patients had unilateral CSOM, involving the right ear in 57 (35.6 per cent) patients and the left ear in 51 (31.8 per cent). Fifty-two (32.5 per cent) patients had bilateral disease.
Predisposing factors
Poverty-related problems (i.e. malnutrition, overcrowding and incomplete immunisation) were found to be the most common predisposing factors in this series, being found to affect 66 (41.3 per cent) patients. Twenty-five (15.6 per cent) of the children were also found to have adenoid inflammation. Cleft palate was seen in four (2.5 per cent) patients. The CSOM was associated with ear trauma in 18 (11.3 per cent) patients, human immunodeficiency virus positivity in four (2.5 per cent), and nasopharyngeal carcinoma in one. Another child had measles with CSOM. The predisposing factor was not known in 41 patients.
Duration of otorrhoea before presentation
Patients' duration of otorrhoea prior to presentation was: two to six months in 32 (20 per cent) patients; seven to 12 months in 21 (13.1 per cent); one to five years in 59 (36.9 per cent); six to 10 years in 39 (24.4 per cent); and 10 years or more in 15 (9.4 per cent).
Previous treatment before presentation
Prior to presentation to a specialist, 54 (33.8 per cent) of the patients had received systemic antibiotics in one form or another; most of these had been procured without prescription. Sixty-one (38.1 per cent) patients had used ear drops, containing either antibiotics or other substances (including ‘holy water’ prescribed by some religious groups, ‘goat nasal discharge’ and honey). Three patients (1.9 per cent) had received some form of injection. Traditional or herbal preparations had been used by nine (5.6 per cent) patients. One patient (0.6 per cent) had undergone incision and drainage of mastoid abscess. Thirty-two (20.0 per cent) of the patients had received no form of prior treatment.
Type of perforation
The majority of patients (153 patients, 95.6 per cent) had a central perforation; of these, 52 had bilateral involvement. Only seven patients had marginal perforations, and these were all unilateral.
Clinical presentation
The majority of our patients (139, 86.9 per cent) had otorrhoea with central perforations alone. Otorrhoea with perforation and granulation tissue (i.e. aural polyp) was the presentation in 16 (10 per cent) patients. Cholesteatoma with otorrhoea was seen in four (2.5 per cent) patients.
Complications
The complications observed are shown in Table II. Figures 1, 2 and 3 are some examples of these complications.
Complications of CSOM seen in children and adults
CSOM = chronic suppurative otitis media
Subperiosteal mastoid abscess with a discharging fistula, complicating chronic suppurative otitis media in a child.
A case of neglected chronic suppurative otitis media complicated by extensive otitis externa and meatal stenosis.
Subperiosteal mastoid abscess complicating chronic suppurative otitis media in an adult.
Disabling hearing loss (i.e. 40 dB and above) was seen in 18 patients (11.3 per cent); 11 (6.9 per cent) were aged above 15 years, while seven (4.4 per cent) were aged 15 years and below. Subperiosteal mastoid abscess was seen in seven cases (4.4 per cent), five (3.1 per cent) of which occurred in children aged 15 years and below. Intracranial suppuration was seen in six (3.8 per cent) patients, all of them children. In all, there were 46 cases of complications, bringing the complication rate to 28.8 per cent.
Treatment
Medical treatment was instituted in 132 patients. This included frequent aural toileting, topical and systemic antibiotics, and nasal decongestants. Only four (22.2 per cent) of those with disabling hearing impairment had hearing aids fitted; others could not afford hearing aids (which were neither affordable nor readily available).
Sixteen (10 per cent) of the patients underwent surgery. Procedures included incision and drainage of subperiosteal mastoid abscess and cortical mastoidectomy in seven patients (4.4 per cent), radical mastoidectomy in two (1.3 per cent), myringoplasty in two (1.3 per cent) and aural polypectomy in five (3.1 per cent). The mortality rate in patients with intracranial suppuration was 100 per cent. Five (83.3 per cent) of these patients died before any treatment could be undertaken, while one underwent a burr-hole procedure for drainage of intracranial abscess and mastoidectomy but died a few hours post-operatively due to overwhelming sepsis. Adenoidectomy was performed in all patients with adenoid inflammation, in addition to medical treatment of their CSOM.
Discussion
Chronic suppurative otitis media forms the greatest clinical burden for the Nigerian otologist. It was found in 11.1 per cent of the studied population, and constituted 21.5 per cent of the otological workload. Over two decades ago, in the south-eastern part of Nigeria, Okafor found that CSOM was the most common ear disease, accounting for 44.8 per cent of patients presenting to their otolaryngology out-patient unit.Reference Okafor1 In 2003, Lasisi et al. found CSOM to be a common problem seen by general practitioners in Ibadan, in south-western Nigeria.Reference Lasisi, Fawole, Usman and Sobode2 In spite of the advent of antibiotics, chronic otitis media is still a relatively common disease in children and constitutes one of the leading causes of functional disability.Reference Mawson and Ludman3 A study performed in a rural community in the middle belt of Nigeria by Ologe et al. found a CSOM prevalence of 7.3 per cent among schoolchildren.Reference Ologe and Nwawolo4 In an epidemiological survey of otitis media within a semi-urban community, Amusa et al. found CSOM to be prevalent in Nigerian children.Reference Ologe and Nwawolo5 Other studies reported that CSOM was common in rural areas in the middle belt of Nigeria,Reference Ologe and Nwawolo6 and among Nigerian schoolchildren.Reference Amusa, Ijadunola and Onayade7
By comparison, CSOM occurs in an estimated 5 per cent of adults in the UK, of whom approximately 2 per cent will have active infection.Reference Browning, Gatehouse and Calder8 An epidemiological study among children in Greenland showed a prevalence of 9–12 per cent.Reference Morris9
The majority of those presenting to our hospital with CSOM lived in rural areas. This underlines the role of poor social economic factors in the prevalence of the disease. The majority of rural dwellers are uneducated and earn a low income, and this contributes to the delay in seeking help for a discharging ear. The rural areas of Nigeria are not adequately provided with health facilities; therefore, a patient's first medical treatment is usually in the form of ‘over the counter’ drugs procured from patent medicine dealers, who are usually unlicensed and untrained. The indiscriminate sale of systemic antibiotics by such dealers promotes bacterial antibiotic resistance.
Patients' lack of funds usually delays their presentation at a hospital or health facility, as money is required for transportation and for medical treatment. This situation contributes to the high rate of complications seen in our patients, including such potentially fatal conditions as subperiosteal mastoid abscess and intracranial suppuration. Such patients present with little or no money for investigations and surgery, and usually when it is almost too late for any intervention. Lasisi et al., working in Ibadan, Nigeria, found that most general practitioners preferred to treat a discharging ear with ear drops, and did not utilise any form of aural toileting or wick dressing.Reference Lasisi, Fawole, Usman and Sobode2
We found that the prevalence of CSOM was highest in the zero to five year age group, and approximately half our CSOM patients were aged between zero and 15 years (Table I). This corroborates the findings of Matanda et al. from the University Clinic of Kinshasa, Democratic Republic of Congo.Reference Matanda, Muyunga, Sabue, Creten and Van de Heyning10 We found that the prevalence of CSOM decreased with increasing age (Table I). This is similar to Okafor's 1984 findings.Reference Okafor11
Otorrhoea was the most common symptom at presentation, followed by hearing impairment. Most of the patients we saw had waited between one and five years before seeing an otologist.
Over 90 per cent of our CSOM patients presented with a large, central perforation, i.e. a ‘safe’ perforation. Attic perforation (i.e. ‘unsafe’ perforation) was not common in our patients. We saw four cases with cholesteatoma, treated with radical mastoidectomy. Tubotympanic disease was seen in 95.6 per cent of patients; this compares well with the figures of 98.8 and 99.8 per cent found by Ologe and Nwawolo, and Okafor, respectively.Reference Ologe and Nwawolo4, Reference Ologe and Nwawolo5, Reference Okafor11 The low occurrence of cholesteatoma seen in our series compares well with the findings of previous studies by OkaforReference Okafor11 and other African authors.Reference Ibekwe and Okoye12, Reference Brobby13 Similar findings have been reported in Australian Aboriginal children, with associated large central perforations and better middle-ear aeration.Reference McCafferty, Lewis, Coman and Mills14
We found complications of CSOM, such as meningitis, intracranial abscess, subperiosteal mastoid abscess and mastoiditis, in 28.8 per cent of patients. Four of these complications (8.69 per cent) were associated with cholesteatoma. Even though the perforations seen were of the safe type, the complication rate was very high, close to 30 per cent. This high complication rate associated with a very high proporation tubotympanic disease compares favorably with Okafor's earlier report of CSOM from eastern Nigeria11. It has previously been thought that more complications are found with attico-antral disease (i.e. the unsafe type of CSOM); however, it appears from our study that complications are also associated with mucosal disease. Intracranial sepsis in patients with tubotympanic disease has also been reported in studies from the developed world,Reference Nunez and Browning15, Reference Browning16 although the risk of developing intracranial sepsis in adults with active CSOM is currently one in 10 000 annually.Reference Nunez and Browning15 Our patients tended to have frequent episodes of prolonged otorrhoea due to neglect and inappropriate treatment, and would often plug their ears with cotton wool balls to hide the discharge. This further worsened the problem, as the discharge was not allowed to drain freely and therefore accumulated. Poor socioeconomic factors and lack of access to adequate health facilities were confounding factors identified amongst our patients.
• In developing countries, chronic suppurative otitis media (CSOM) is usually of the ‘safe’ type, as cholesteatomas are less often seen. Large, central perforations allow aeration of the middle ear
• In developing countries, inadequate treatment of CSOM due to poor socioeconomic factors predisposes to complications, which can be fatal
• In communities such as these, how safe is ‘safe’ CSOM?
Children suffer more complications of CSOM than adults. This finding was also noted by Liang et al., working in China.Reference Liang, Chen, Ou, Ding, Xu and Yang17 Factors such as overcrowding, low socioeconomic status, malnutrition and poor access to immunisation may have contributed to a higher prevalence of CSOM amongst our younger patients. This is similar to the findings of Fliss et al. who reported an increased risk of CSOM in association with larger families, more siblings, a higher crowding index and care in large day care centres.Reference Fliss, Shoban, Leiberman and Dagan18
Amongst our patients suffering CSOM complications, mortality was 100 per cent in those who developed intracranial abscesses. This occurred despite exploration and neurosurgical consultation, due to late presentation and patients' inability to afford radiological investigations and antibiotics. These deaths could have been prevented.
Since the problem of late presentation was seen more among rural patients, early recognition of danger signs and prompt referral of otological cases are to be incorporated into the training of primary healthcare providers within these communities.
Disabling hearing loss (40 dB and above) was found in 11.3 per cent of our patients. This was mainly of the conductive type; sensorineural loss was seen in less than 3 per cent of the studied group.
The majority of our patients were treated medically; this was mainly due to the fact that patients could not afford surgery. Patients who were advised for myringoplasty mostly opted to use a hearing aid instead, which most of them could still not afford. Subperiosteal abscess and intracranial suppuration were the major indications for surgery in our patients. Surgery was performed in 10 per cent of our patients. This is a low rate compared with the work of Matanda et al. in Kinshasa, Democratic Republic of Congo, who performed mastoidectomy on 55 per cent of their patients.Reference Matanda, Muyunga, Sabue, Creten and Van de Heyning10 This was because surgery could not be afforded by most of our patients. Therefore, myringoplasty was performed in two of our patients, although many more would have benefited from it. In addition, cortical mastoidectomy was performed in five patients.
Conclusion
In Nigeria, patients with CSOM often present to tertiary health care facilities late, and often after receiving unhelpful prior treatment. The problems of late presentation and poverty compound the clinical problems and increase morbidity and mortality. Improving healthcare facilities in rural areas would reduce the incidence of CSOM complications seen in this study.
