Odontogenic Actinomycotic Necrotizing Fasciitis of Cervicothoracic Region: A Case Report

Abstract

We report an uncommon odontogenic actinomycotic cervicothoracic Nectrotizing Fasciitis (NF), treated with tracheostomy, immediate surgical debridement and antibiotics. Red flags for early identification, LRINEC scoring for prognostication, surgical debridement with aerobic & anaerobic culture specific antibiotics to improve survival in this life-threatening cervicothoracic NF in a young diabetic is discussed.

Introduction

Commonly originating from odontogenic infections, Cervicofacial necrotizing fasciitis is a rapidly progressive potentially fatal infection of soft tissues, incidence of 1–10% cases [1, 2]. “Necrotizing fasciitis” (NF) coined by Wilson in 1952 has mortality rate as high as 40% [3]. Early identification, surgical intervention, and specific antibiotics improves survival.NF is commonly polymicrobial in nature especially streptococcus due to uncontrolled diabetes mellitus and nutritional deficiencies. Actinomyces, gram positive anaerobic-to-microaerophilic commensal bacteria in genitourinary and gastrointestinal tract, rarely causes NF of head & neck [4–6].

Case Report

A 40-years uncontrolled diabetic lady presented with painful rapidly progressive left-sided neck swelling for 5 days following left lower toothache with no fever, breathing or swallowing difficulty.

A 6 × 6 cm diffuse swelling in left side of neck extending from mandible, anteriorly from mentum to posterior border of left sternocleidomastoid, superiorly from inferior border of mandible till thyroid cartilage with induration till 2nd rib was present. Skin over the swelling was erythematous & tense with central necrotic eschar of size 3 × 3 cm, minimal serosanguinous discharge in submandibular area and left lower 2nd molar caries tooth was noted on clinical examination.

USG neck showed ill-defined heterogenous hyperechoic subcutaneous zone of 3.4 × 2.4 × 1.4 cm in left cervical region Fig. 1.

Fig. 1.

CECT neck, chest- 4.4 × 5.3 × 6.6 cm ill-defined non-enhancing hypodense collection with multiple air pockets in submandibular region infiltrating left mylohyoid, overlying skin, extending to anterior chest wall, tracking along anterior triangle of neck upto thyroid gland, infiltrating sternomastoid, thyrohyoid and sternohyoid muscles, parasymphysial aspect of mandible, suggestive of myofascitis

Diagnosed as cervicothoracic Necrotizing Fasciitis of Odontogenic origin, she was treated empirically with IV Amoxiclav & Metronidazole, elective tracheostomy, Incision & drainage of 30 ml pus and wound debridement from mandible upto level of 2nd rib, via transverse neck incision under general anaesthesia. 30 ml pus was drained and offending tooth extracted by dental surgeon. Histopathological examination showed fascial necrosis, pus culture & sensitivity showed growth of Actinomycetes species in anaerobic medium but no growth in aerobic culture Fig. 2.

Fig. 2.

Pre-operative appearance, tracheostomy, surgical debridement, twice daily dressing with Povidone Iodine and Hydrogen-peroxide irrigation, followed by local metronidazole wash. By seventh-day healthy granulation was noted. Patient decannulated on POD 10 oral antibiotics for 2 weeks, healed neck

On POD 14 plastic surgery opinion obtained for wound closure and was advised grafting. However, she was not willing for same, so advised daily dressing at local health centre which healed the wound by secondary intention, without contracture in a fortnight.

Discussion

NF, a rare, life-threatening infection causing rapidly progressive necrosis of subcutaneous fat, fascia, muscle and subsequently overlying skin having a highly septic clinical presentation with poor prognosis.Usually occurs secondary to odontogenic infections in head & neck worsened by immunocompromising factors like diabetes, alcoholic liver disease, atherosclerosis, malnutrition, metastatic neoplasms, chronic renal failure and polymyositis [2, 3]. NF may also follow minor trauma [6].

Disproportionately severe pain, extending beyond swelling, predicting extent of NF is a distinctive feature. Initial erythema and swelling, induration, fluctuation and blister formation later, purple spots, dark haemorrhagic blisters, complete anaesthesia of affected skin with crepitus and dusky skin necrosis is pathognomonic of NF [2, 3, 5]. In immunocompromised, inadequately treated patients, necrosis can progress to frank gangrene leading to sepsis with high mortality. [2, 3, 5, 7].

Laboratory Risk Indicators for Nectrotizing fasciitis (LRINEC) Scoring system with highest positive (92%) and negative (96%) predictive values are useful for detection of early NF with severe soft tissue infections, suspicion of NF if score is > 6, and > 8 indicating strong predicition of NF [6, 8] Table 1.

Table 1.

Lrinec scoring

Parameters	Scores	Our patient
C-reactive protein mg/L	0
<15
>/= 15	4	133 (4)
Total white blood cell count (per mm3)
<15
15-25	0
>25	1	15,400 (1)
	2
Haemoglobin (g/dl)
>13.5	0
11-13.5	1	9.9 (2)
<11	2
Sodium (mmol/l)
>/=135	0
<135	2	134 (2)
Creatinine (mg/dl)
</=1.6	0	0.6 (0)
>1.6	2
Glucose (mg/dL)
<180	0
>180	1	239 (1)
TOTAL	>5- low risk	9- HIGH RISK
	6-8 - intermediate risk
	>8 – high risk

CT scan of NF demonstrates fascial thickening (potential fat stranding), oedema, subcutaneous gas, and abscess formation. MRI has shown 100% sensitivity and 86% specificity, though MRI may not show early fascial involvement of NF. CECT head, neck and thorax shows extent of involvement [9].

Only 15–34% of patients with NF have an accurate admitting diagnosis. The key points are clinical suspicion, intervention by broad spectrum antibiotics and early surgical debridement which confirms the diagnosis of NF. LRINEC Scoring serological markers help in prognostication. [6]

Debridement of necrozed tissues (skin, fascia, fat and muscle) is vital along with collection of repeat samples for microbiological and histopathological examination. Odontogenic cervicofacial NF is usually polymicrobial from oral cavity, typically alpha-hemolytic streptococci and obligate anaerobes as Prevotella spp. & Bacteroides spp. [1] Early broad-spectrum antibiotics and surgical debridement are keys to good prognosis.

Our patient underwent surgical debridement and tracheostomy in view of threatened airway, along with IV antibiotics on the day of presentation. Serial debridement & wound care with povidone iodine, hydrogen peroxide and metronidazole aided epidermal migration and neoangiogenesis in the moist wound bed thereby healing rapidly. Moist wound heals better giving good cosmesis, reduces pain, with healthy wound granulation [10]. Microbial culture revealed Actinomycetes species in anaerobic culture with no growth in aerobic culture, showing the requirement for anaerobic cultures so as to detect unusual pathogenic organisms. With meticulous wound care, strict control and administration of appropriate antibiotics good healing was achieved without grafting, or contracture or dysfunction.

Conclusion

NF should be considered in diffuse soft tissue infections especially in diabetes mellitus. Poor socioeconomic status, nutrition, awareness of dental infections, delay in referrals and distance to tertiary care centres pose increased morbidity to atypical infections like Actinomycotic NF which can rapidly progress to mortality. Prompt evaluation, LRINEC scoring for diagnosis and prognosis, aerobic and anaerobic culture of pus or necrotic tissue, initiation of medication and surgical debridement along with scrupulous postoperative care are crucial to improve outcome of our patient with cervicothoracic NF.

Funding

Not applicable.

Declarations

Conflicting Interests

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