|Ahead of print publication
Retropharyngeal abscess in a 3-month-old infant: A rare entity
Inderdeep Singh1, Tanuj Madan2, Amit Rai3, Ashok Yadav4, Rajeev Sivasankar5, Renu Rajguru6, Mohammad Zubair Akhtar7
1 Professor, Department of ENT, INHS Asvini, Mumbai, Maharashtra, India
2 Junior Resident (II), Department of ENT, INHS Asvini, Mumbai, Maharashtra, India
3 Professor, Department of Anesthesiology, INHS Asvini, Mumbai, Maharashtra, India
4 Professor, Department of Paediatrics, INHS Asvini, Mumbai, Maharashtra, India
5 Professor, Department of Radiodiagnosis, INHS Asvini, Mumbai, Maharashtra, India
6 Professor, Department of ENT, INHS Asvini, Mohammad Zubair Akhtar – Junior Resident (I), Mumbai, Maharashtra, India
7 Department of ENT, INHS Asvini, Mumbai, Maharashtra, India
|Date of Submission||15-Jan-2020|
|Date of Decision||12-Feb-2020|
|Date of Acceptance||30-May-2020|
|Date of Web Publication||17-Sep-2020|
Department of ENT, INHS Asvini, Near RC Church, Colaba, Mumbai - 400 005, Maharashtra
Source of Support: None, Conflict of Interest: None
Retropharyngeal abscess (RPA) is a rare infective pathology of deep neck spaces affecting young children and adults. In view of scarce literature availability and atypical presentation in infants, often lacking fever or lymphadenopathy, it poses a definitive diagnostic dilemma to the clinicians. It should be kept in mind for all infants presenting with respiratory distress. History should be carefully taken for any upper respiratory tract infections or nasal discharge preceding the illness. Prompt airway control is of paramount importance, since there is a higher prevalence of airway compromise in infants and early surgical intervention is therefore indicated. Usually, intraoral approach is sufficient for incision and drainage. Here, we present a rare case of RPA in a 3-month-old infant in whom early radiological investigations, especially contrast-enhanced computerized tomography/noncontrast head computerized tomography helped not only in timely diagnosis but also in planning of surgery. A multidisciplinary, integrated strategy of pediatrician, neurosurgeon, microbiologist, radiologist, and otorhinolaryngologist is ideal for patient care.
Keywords: Methicillin-resistant Staphylococcus aureus, nodes of rouviere, retropharyngeal abscess, retropharyngeal space
| Introduction|| |
Retropharyngeal space extends from the skull base to the mediastinum till the first or second thoracic vertebrae. Its anterior boundary is formed by the buccopharyngeal fascia (middle layer of the deep cervical fascia), lateral boundary by carotid sheath with its neurovascular contents, and posteriorly bounded by the alar fascia (deep cervical fascia). Retropharyngeal abscess (RPA) is a rare infection of deep neck space mainly affecting children. In pediatric cases, it presents at an average age of 3.7–5.1 years. RPA is relatively uncommon in infants under 6 months and may present differently compared to older children due to their underdeveloped immune systems. The present literature on RPA is scarce and available only in the form of case reports. The incidence of RPA in infants is not reported. The youngest age in infants developing RPA reported in literature is 4 months. The most common etiology is infective with subsequent abscess formation in retropharyngeal lymph nodes draining nasopharynx, adenoids, posterior nasal sinuses, and posterior nasal cavity. Its clinical presentation is nonspecific and can mimic meningitis, epiglottitis, and foreign body aspiration. Even in presence of complications, neurological and localizing symptoms may not be seen. Patients may present with fever, sore throat, drooling of saliva, wry neck, dysphagia, neck swelling, and trismus. It has the potential to cause remarkable morbidity and mortality with possible complications such as airway compromise, pneumonia, sepsis, mediastinitis, carotid artery aneurysm, and internal jugular vein thrombosis. In adult patients, there is often a history of cervical spine trauma, instrumentation like endoscopy, foreign body ingestion, or any underlying illness such as chronic alcoholism, diabetes, malignancy, immunodeficiency, or cervical spine tuberculosis.
With availability of advanced radioimaging modalities, early diagnosis, and effective antibiotic regimen, RPAs now rarely lead to long-term complications. Increased availability of computed tomography (CT) scanning confirms its diagnosis quite early during the pathogenesis. Early surgical drainage by transoral or transcervical route is the most well-established and widely accepted treatment despite improved antibiotic therapy.
| Case Report|| |
A 3-month-old male infant was transferred from a peripheral hospital with a complaint of noisy breathing for the last 3 days. It was insidious, exaggerated with activity, and reduced when sleeping. There was no fever, regurgitation, drooling of saliva, and vomiting after breastfeeding. The infant had difficulty in breathing when taking feeds and a history of nasal discharge without fever 2 weeks back.
The infant was playful having inspiratory stridor with suprasternal and subcostal chest retractions. Capillary refill time was <3 s, and SpO2 at room air was 97%. X-ray of neck (lateral view) revealed thickened prevertebral shadow (12 mm at C3 level) with airway narrowing in upper airway tract. Hemoglobin was 8.8 g% and total leukocyte count was 24,700/mm3. C-reactive protein was positive and blood culture was negative. The patient was initially managed as croup with intravenous ceftriaxone and nebulization.
When there was no clinical improvement, a contrast-enhanced computerized tomography (CECT) neck was done in civil which revealed a well-defined, lobulated, nonenhancing cystic lesion (22 HU) with minimal rim enhancement (1.7 cm × 1 cm × 2.1 cm) in retropharyngeal space (L) side extending from C1 to C4 with inferior extension up to level of (L) pyriform sinus. The lesion was indenting and compressing adjacent nasopharyngeal air column [Figure 1]. Since the initial CECT Neck was done 3 days back at a peripheral hospital which provided only one film without any digital optical disc, we had to repeat noncontrast head computerized tomography (NCCT) neck to ascertain any increase in size of the collection, its exact extent, and further involvement of any other deep neck space. The extent was from nasopharyngeal region to pyriform sinus (L) with maximum bulge at oropharyngeal airway just below vallecula. Since radiological modalities are complimentary to each other rather than being exclusive and collections in neck which are isodense on CT are also delineated on ultrasound (USG) due to their echogenicity, USG neck was also done with the advice of radiologist. It revealed a homogenous collection in (L) upper retropharyngeal space and the exact location of maximum bulge at the posterior pharyngeal wall where the incision was required to be given.
|Figure 1: Contrast enhanced computerized tomography neck revealed a well defined, lobulated, nonenhancing cystic lesion (22HU) with minimal rim enhancement (1.7 cm × 1 cm × 2.1 cm) in retropharyngeal space (L) side extending from C1 to C4 with inferior extension upto level of (L) pyriform sinus. Lesion was indenting and compressing adjacent nasopharyngeal air column. (Differential diagnoses: Branchial cleft cyst, foregut duplication cyst, (L) retropharyngeal Abscess|
Click here to view
The decision for urgent intraoral transpharyngeal incision and drainage (I and D) under General Anaesthesia (GA) was taken as the child was in stridor. The patient underwent I and D under GA after fiberoptic guided orotracheal intubation. Tracheostomy was also considered in view of anticipated failed intubation or any resultant hemorrhage when attempting intubation. I and D was preferred over aspiration as the child was in stridor and it was imperative for quick resolution of symptoms, prevention of further airway complications, and prompt reduction of infection load. The bulge was at (L) posterior pharyngeal wall below vallecula extending up to (L) pyriform fossa. Base of tongue was not involved. An incision with 0.5 cm depth was given at the point of maximum bulge and the opening was widened. Dissection was extended with periosteal elevator and artery forceps in retropharynx about 1.5 cm towards left pyriform sinus to drain pus with suction [Figure 2]. 15–20 ml frank yellowish pus was drained by putting inside suction tip up to laryngeal level [Figure 3]. Feeding tube was inserted on operation theatre (OT) table itself and antibiotic cover was upscaled by addition of vancomycin. Postoperatively, the inspiratory stridor disappeared with reduction of total leukocyte count to 9400/mm3. Breastfeeding was started after 48 h after inspecting and ensuring healing of incision site. Ryle's tube was removed on 2nd postoperative day once the child tolerated breastfeed comfortably. Gram stain of drained pus smear revealed Gram-positive cocci and pus culture revealed methicillin-resistant Staphylococcus aureus (MRSA) colonies. Acid-fast bacilli on Ziehl–Neelsen stain and culture based nucleic acid test were negative. NCCT neck was also repeated 1 week later which revealed no fresh collection [Figure 4].
|Figure 4: Postoperative day 7. Repeat noncontrast head computerized tomography shows minimal oedema with no fresh collection|
Click here to view
| Discussion|| |
The retropharyngeal space includes lymph nodes which drain the nasopharynx, adenoids, and paranasal sinuses. These are lateral lymph nodes (of rouviere) which are four to five in number and disappear by 5 years of age. Suppuration of these lymph nodes following upper respiratory tract infections/nasal infections leads to abscess formation. Boys have a higher incidence of deep neck space infections than girls (60%). Usual clinical picture shows neck swelling, sore throat, wry neck, loss of appetite, oropharyngeal bulge with hyperpyrexia, and stridor. Infection in most deep neck abscesses is usually polymicrobial including aerobes such as Staphylococcus, Streptococci pneumoniae, Haemophilus influenza and anaerobes like Bacteroides, Prevotella, Peptostreptococcus, Fusobacterium, Clostridium sp. At present, MRSA is the most frequent pathogen with a culture positivity of 38%. In a previous 11-year study, culture positivity rates of Group A Beta Hemolytic Streptococci were as high as 33% as compared to 3% of MRSA. In an Indian study by Showkat et al., MRSA was found to be the most common bacteria isolated from various deep neck abscesses and was seen in 50% of culture positive patients (20 out of 41) and 40% in overall patients. Rarely, Gram-negative bacteria or nonpyogenic microorganisms such as Mycobacterium tuberculosis, Brucella More Details, or fungi were also reported as the causative agents. Direct extension of an abscess and hematogeneous seeding are other pathways.
Infants pose a substantial diagnostic challenge due to their immature immune systems leading to an unusual presentation. As per review of available publications on RPA in infants, it was deduced that fever was seen in approximately 27% of infants and around 77%–90% of older children. Airway symptoms were present in 71% of infants and approximately 43% of older children. Airway obstruction in RPA is more common in younger age (mean age - 1.4 years). Children without airway symptoms present at an average age of 3.6 years. Since there is higher incidence of airway affection in infants, prompt intervention in this subset of patients is highly recommended. Complications of RPA are mediastinitis, airway obstruction, pneumonia, sepsis, carotid artery aneurysm, and jugular vein thrombosis. In older children, RPA cases secondary to vertebral osteomyelitis, foreign bodies in upper aerodigestive tract, and neck trauma have also been reported. RPA can also present with neurologic deficits like limb paresis/paresthesia, unstable gait and loss of bladder control. These symptoms are less marked in infants.
X-ray cervical spine is the initial radiological investigation for diagnosis. On plain X-ray, a prevertebral space thickness of <6 mm at C3 level in children and in adults thickness up to 6 mm at C2 and 22 mm at C6 is considered within normal limits. However, in our case, the prevertebral soft tissue shadow thickening was 12 mm at C3 level which was surely pathological. CT scan is preferable as it delineates and maps out the abscess location, extent, its relationship to vital structures, and complications. CT-guided drainage of RPAs is also documented. RPA in 3-month-old infant is rarely reported in literature.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Elsherif AM, Park AH, Alder SC, Smith ME, Muntz HR, Grimmer F. Indicators of a more complicated clinical course for pediatric patients with retropharyngeal abscess. Int J Pediatr Otorhinolaryngol 2010;74:198-201.
Katavić M, Štefanović I, Vrsalović R, ZlatićGlogoški M, Tešović G, Baudoin T. Retropharyngeal abscess in a four month old female infantcase report. Int J Pediatr Neonatal Care 2016;2:121.
Johnston D, Schmidt R, Barth P. Parapharyngeal and retropharyngeal infections in children: Argument for a trial of medical therapy and intraoral drainage for medical treatment failures. Int J Pediatr Otorhinolaryngol 2009;73:761-5.
Baldassari CM, Howell R, Amorn M, Budacki R, Choi S, Pena M. Complications in pediatric deep neck space abscesses. Otolaryngol Head Neck Surg 2011;144:592-5.
Harkani A, Hassani R, Ziad T, Aderdour L, Nouri H, Rochdi Y, et al
. Retropharyngeal abscess in adults: Five case reports and review of the literature. Sci World J 2011;11:1623-9.
Rahman M, Savage JR, Lee CA. Spontaneous descending retropharyngeal abscess. BMJ Case Rep 2009;2009. pii: bcr10.2008.1034.
Hasegawa J, Hidaka H, Tateda M, Kudo T, Sagai S, Miyazaki M, et al
. An analysis of clinical risk factors of deep neck infection. Auris Nasus Larynx 2011;38:101-7.
Vinograd AM, Zonfrillo MR, Pawel B. Retropharyngeal abscess and mediastinitis in a well-appearing infant with prolonged fever. Pediatr Emerg Care 2017;33:43-6.
Jain A, Singh I, Meher R, Raj A, Rajpurohit P, Prasad P. Deep neck space abscesses in children below 5 years of age and their complications. Int J Pediatr Otorhinolaryngol 2018;109:40-3.
Abdel-Haq NM, Harahsheh A, Asmar BL. Retropharyngeal abscess in children: The emerging role of group a beta hemolytic streptococcus. South Med J 2006;99:927-31.
Showkat SA, Dar FA, Shaf OM, Patigaroo SA, Ahmed R. Deep neck space abscesses in children and methicillin resistant Staphylococcus aureus
(MRSA) as an emerging pathogen – A clinical study. Int J Curr Microbiol Appl Sci 2020;4:1087-97.
Metin Ö, Öz FN, Tanır G, Bayhan Gİ, Aydın-Teke T, Gayretli-Aydın ZG, et al
. Deep neck infections in children: Experience in a tertiary care center in Turkey. Turk J Pediatr 2014;56:272-9.
Bagatell SJ, Weimer SM, van Dyke RB, Bracey SV. Neck pain. Clin Pediatr (Phila) 2007;46:280-1.
Ali NE, Alyono JC, Koltai PJ. Neonatal retropharyngeal abscess with complications: Apnea and cervical osteomyelitis. Int J Pediatr Otorhinolaryngol 2019;126:109613.
Debnam JM, Guha-Thakurta N. Retropharyngeal and prevertebral spaces: Anatomic imaging and diagnosis. Otolaryngol Clin North Am 2012;45:1293-310.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]