Materials and Methods:
The Institutional Ethics Committee approved this prospective
observational study on 70 patients of SBO of our institute (IRB-AIMS
2018−029). The ethical standards in the Declaration of Helsinki have
been adhered to. All investigations and interventions were performed
with the informed consent of the patient. The study and reporting
followed the guidelines of ICMJE (International Committee of Medical
Journal Editors- http://www.icmje.org) and COPE (Committee on
Publication Ethics).
Inclusion criteria:
(Medical group) Patients of SBO who responded to antimicrobial therapy
alone.
(Surgical group) All patients of refractory SBO who did not respond to
at least four weeks of systemic antibiotic therapy and were fit to
undergo surgery.
Diagnosis of SBO requires the presence of clinical features and imaging
( CECT- Contrast Enhanced Computed Tomography or MRI- Magnetic Resonance
Imaging )as per Cohen and Friedman criteria.10Clinical features like pain, edema of the canal wall, ear discharge, and
granulations were documented. Ear discharge and granulation tissue from
the ear and nasopharynx were sent for culture and biopsy. Weekly
checking of inflammatory markers [ C- Reactive Protein(CRP) and
erythrocyte sedimentation rate(ESR)] was done till the patient became
asymptomatic. Later, markers were checked at an interval of two weeks
till they became standard value, resulting in the stoppage of
antimicrobials. Antibiotics were administered through a PICC line
(peripherally inserted central catheter). Relief from pain was
considered an initial indicator of response to antibiotics. Patients who
completed treatment with medications alone were categorized as the
medical group. Those who continued to have pain despite four weeks of
systemic antibiotic treatment were considered refractory and were
offered surgical debridement (surgical group).
Medical group: All patients were treated with culture-directed
antibiotics whenever possible. Culture included direct biopsy and
culture of granulations from the ear canal and nasopharynx performed in
the outpatient section. All culture-negative patients were empirically
started either on intravenous (IV) Ceftazidime (2g per dose 12th hourly)
or Piperacillin-Tazobactum (4.5g 8th hourly) combined with IV or oral
Ciprofloxacin (IV − 400 milligrams [mg] 12th hourly, oral- 750mg
12th hourly). Antibiotics were changed after one week if the patient
continued to have pain. Antifungal therapy was initiated when the
patient did not respond after changing antibiotics twice or thrice.
Intravenous Voriconazole at a loading dose of 6 mg/kg 12th hourly for
two doses was followed by intravenous at 3 mg/kg or oral 200 mg 12th
hourly as a maintenance dose.
Surgical group: Surgical option was given to patients with no pain
relief after a minimum of four weeks of IV antimicrobial therapy. The
surgery aimed to obtain deep tissue for culture and to reduce the
microbial load as much as possible. All consenting patients underwent
complete or partial debridement under general anaesthesia based on CT or
MR imaging. Antimicrobials were changed if the surgery yielded culture.
Otherwise, advice from the infectious diseases department was followed.
The extent of debridement could be a mastoidectomy; subtotal
petrosectomy with disease clearance from the tympanic ring, anterior
canal wall, facial canal, jugular foramen, carotid canal, eustachian
tube or petrous apex. The temporomandibular joint; parotid;
parapharyngeal space, infratemporal fossa, nasopharynx, sphenoid, clivus
or greater wing of the sphenoid were debrided in some cases. In some
patients, only partial debridement was possible due to difficult access.
Histopathology and cultures for fungus, bacteria, and acid-fast bacillus
were done. In those already on multidrug therapy, a DNA-PCR with gene
sequencing improved the yield.11
In both groups, treatment ended when the inflammatory markers remained
normalized for six weeks in a symptom-free patient. After the initial
scan, CT or MRI scans were done only for new symptoms. Radiological
follow-up was with 32 FDG - PET CT (Fluorodeoxyglucose- Positron
Emission Tomography) scans in all cases. Usually, it confirmed disease
clearance at the end of 6 to 8 weeks of treatment if the patient was
asymptomatic. If possible, the PET scan was repeated every 8 to 12 weeks
when the treatment became prolonged. At the end of the study period of
26 months, there were 35 patients in the surgical group. First, 35
patients who completed medical treatment comprised the medical group. We
used absent activity in PET scans as an indicator of cure in our
patients.7 The rapidity of relief from pain, ear
discharge, edema of the ear canal, granulations, and duration of
treatment in both groups were evaluated. For the medical group, the
entire duration of antimicrobial treatment was taken. For the surgical
group, the duration of treatment included the initial antimicrobial
therapy, the surgery, and postoperative therapy. The antimicrobial
treatment before surgery ranged from 4 weeks to 36 weeks. Follow-up
ranged from 12 weeks to 26 months.
Statistical analysis:
Statistical analysis was done using the IBM SPSS Statistics 20 Windows
(SPSS Inc., Chicago, USA). The results are given in mean ± SD for all
the continuous variables and frequency (percentage) for categorical
variables. To test the normality of the data, the Kolmogorov-Smirnov
test was applied. Independent sample t-test and Mann-Whitney U test were
applied to compare the two groups’ mean/ average of continuous
parameters. A p-value < 0.05 was considered statistically
significant. All tests of statistical significance were two-tailed.