Group B and F Beta Streptococcus Necrotizing Infection Surgical Challenges with a Deep Central Plantar Space Abscess

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1 CLINICALLY SPEAKING Group B and F Beta Streptococcus Necrotizing Infection Surgical Challenges with a Deep Central Plantar Space Abscess A Diabetic Limb Salvage Case Report Jason M. Mendivil, DPM* David Jolley, DPM* Jodi Walters, DPM* Jim Dancho, DPM* Billy Martin, DPM* We present the case of a 66-year-old, type II diabetic male with a deep wound to the plantar-lateral aspect of his right hallux. On examination, the central plantar compartment of his right foot was moderately erythematous and tender on palpation. After obtaining a deep wound culture, treatment was complicated by a progression of a group B and F beta streptococcus, necrotizing infection. The patient underwent a right hallux amputation, followed by a plantar medial incision for drainage of an abscess to the medial and central plantar compartments of the foot. Due to the extent and limb threat of the infection, the patient ultimately underwent a transmetatarsal amputation. Advanced healing modalities were also employed to decrease wound healing times, which allowed the patient to achieve early weightbearing and return to activities of daily living. This study depicts how the astute podiatric surgeon needs to make a decision in a timely manner to surgically debride all nonviable and necrotic tissue in order to minimize further amputation and preserve foot function. (J Am Podiatr Med Assoc 106(3): , 2016) Necrotizing fasciitis is a rare infection of the deeper layers of skin and subcutaneous tissues. Patients who are immunocompromised are at a greater risk for prolonged infection. Immediate treatment with surgical debridement and high doses of intravenous antibiotics decreases the probability of a more proximal amputation. 1 Surgical intervention may be necessary to prevent rapid spreading through fascial planes of the foot and proximal tracking along tendons. 2 When the central plantar space of the foot is infected, the tendons of the flexor digitorum longus, flexor digitorum brevis, quadratus plantae, and the lumbricales are at risk. 3 A group B and F beta streptococcus bacterial infection can complicate wound healing when spreading throughout the plantar foot compartments. *Departments of Surgery and Podiatric Surgery, Southern Arizona Veteran Affairs Health Care System, Tucson, Arizona. Corresponding author: Jason M. Mendivil, DPM, Departments of Surgery and Podiatric Surgery, Southern Arizona Veteran Affairs Health Care System, 3601 S 6th Avenue, Tucson, AZ ( jasonmendivildpm@yahoo.com) The taxonomy discussed here is of the group F streptococcus, also referred to as the streptococcus milleri (or S anginosus) group. This taxonomy is in accordance with the Lancefield Classification System. 4 This group consists of three separate types of species, including S anginosus, S intermedius, and S constellatus. These groups are nonhemolytic and were initially isolated from dental abscesses by Guthoff 5 in The group F streptococcus group was initially described by Long and Bliss 6 in Group F streptococci are found normally as oral and gastrointestinal tract flora, with a unique predisposition to develop deep abscesses and systemic infections. Group F streptococcus strains are nonmotile, gram positive, catalase-negative cocci. These organisms possess cell surface adhesions that are fibronectin binding. Pathogenesis of the organism is characterized by a polysaccharide capsule that is resistant to phagocytosis from a host. Group F streptococcus strains also produce pyrogenic exotoxins and hydrolytic enzymes (hyaluronidase) that facilitate the spreading through fascial tissue planes of the foot, which can cause 218 May/June 2016 Vol 106 No 3 Journal of the American Podiatric Medical Association

2 liquefaction necrosis of the tissues. Treatment for deep tissue abscesses and blood infections caused by this organism consists of surgical consideration with incision, drainage, and antimicrobial therapy with a third-generation cephalosporin; these organisms are susceptible to beta-lactam antibiotics. Group F streptococci have been shown to cause periodontal disease and odontogenic abscesses. 7 The group F streptococcus bacteria can form abscesses, commonly affecting the cutaneous system. It is often associated with trauma to tissues. This organism also can cause infections in the immunocompromised and the elderly, 8 as seen here in the present case. Group F streptococcus is mostly susceptible to penicillin antibiotics. This organism has also been found to be a typical organism found in cases of endocarditis, as illustrated by Righter and Zwerver. 9 Junckerstorff et al 10 also investigated an association between the different species types of group F streptococcus (streptococcus intermedius, streptococcus anginosus, and streptococcus constellatus) and clinical results and length of hospital stay. They concluded that identifying the group F streptococcus to its taxonomic level may be beneficial, with infections caused by streptococcus intermedius having a significantly longer hospital stay than infections caused by streptococcus anginosus. 10 Group B streptococcus is also referred to as the streptococcus agalactiae group. It is known to colonize the human genitalia and gastrointestinal tract. It can cause infection in neonates, pregnant women, and in adults with chronic medical conditions, including diabetes mellitus. It can cause infection in the elderly patient population (older than 65 years of age). The capsule of this species serves as a virulence factor. Ogawa et al 11 discussed the successful treatment of a necrotizing infection in patients with diabetic nephropathy. In their case study, a group B streptococcus was cultured from tissue and blood cultures resulting from a skin lesion in the thigh of a patient with diabetic nephropathy. This organism is usually not the culprit in cases of a necrotizing fasciitis, but it was shown in their study to infect both the superficial fascial layer and underlying muscle tissue. This was one report, of a few, to show how a group B streptococcus can cause a necrotizing infection in patients with diabetes mellitus. Histologic examination of the tissue showed neutrophil infiltration and vascular degeneration, which are consistent with a necrotizing fasciitis diagnosis. The patient in this case was treated with intravenous antibiotics and surgical debridement. A necrotizing infection can be fatal unless aggressive management with surgical debridement to remove the focus of infection and intravenous antibiotics is employed. A C-reactive protein value greater than 20 mg/dl is also suggestive of a necrotizing infection. 11 The authors in this case study conclude that necrotizing fasciitis may also be frequent in patients with diabetes due to microvascular disease and resulting tissue hypoxia. 11 In a case study with a necrotizing fasciitis and toxic shock like syndrome caused by a group B streptococcus, Holmström and Grimsley 12 exhibited that clindamycin has been shown to inhibit group B streptococcus infections (as in group A streptococcus infections). They employed the use of hyperbaric oxygen therapy to treat infection by group B streptococcus but have concluded that future research is needed. 12 Case Report A 66-year-old male with a past medical history of uncontrolled type II diabetes presented to the emergency department at the Southern Arizona VA Health Care System Hospital, Tucson, Arizona. He was evaluated for a 2-month history of a painful wound to the bottom of his right hallux, swelling, and erythema to the plantar medial aspect of his right foot. He was self-managing the wound for about 2 months prior and decided to seek medical care because of unbearable pain. He soaked his foot in Epsom salt and applied triple antibiotic ointment daily prior to his hospital visit. He denied receiving any type of medical care for 40 years. He reported having fever and chills, as well as an allergy to penicillin. Right foot series radiographs taken during the time of admission were suggestive of osteomyelitis to the right hallux, with an extensive soft-tissue infection. Operative Procedure and Hospital Course The patient s white blood cell count was /lL; HbA 1c, 12.1%; C-reactive protein, 171 mg/l; and erythrocyte sedimentation rate 88 mm/h. He was febrile in the emergency department, and was placed on intravenous vancomycin, ciprofloxacin, and metronidazole on admission. A 2-cm stab incision and drainage slightly proximal to the right first interspace was performed bedside, followed by wound debridement. A right hallux amputation, pulse lavaged with 3L of normal saline and bacitracin solution was performed. In addition, the Journal of the American Podiatric Medical Association Vol 106 No 3 May/June

3 wound to the plantar aspect was packed open with vancomycin- and gentamicin-impregnated beads intra-operatively. During the hallux amputation, necrotic and foul smelling tissue was noted lateral to the first metatarsal in the central compartment of the foot, suggestive of further infection. Microbiology results from an intra-operative bone culture were remarkable for mixed flora, including beta streptococcus group B and group F. The amputated hallux was sent to surgical pathology for evaluation, which was remarkable for fibrosis, chronic inflammation of the soft tissue, and chronic osteomyelitis. Following the hallux amputation, the patient continued with a mild leukocytosis and a low-grade fever. The patient complained of moderate pain to the plantar medial aspect of his right foot. An infectious disease consultation was placed for a necrotizing infection, and the patient was placed on intravenous clindamycin, followed by oral moxifloxacin. A plantar medial incision and drainage was performed in the clinic to remove further abscess and nonviable tissue (Figs. 1 and 2). Surgical debridement of necrotic tissue and intra-operative exploration of the three main compartments of the foot was performed. The patient underwent a subsequent transmetatarsal amputation with a penrose drain (Figs. 3-7). The forefoot excision specimen was sent to surgical pathology, which showed gangrenous necrosis and ulceration of the Figure 2. Clinical photograph showing subcutaneous necrosis 3 days after right foot hallux amputation and incision and drainage. The intra-operative bone culture was positive for beta strep group B and beta strep group F. soft tissue and bone. An extracellular matrix dressing to promote wound healing was packed into the plantar wound during the course of treatment. The patient started walking with a CAM Figure 1. Clinical photograph showing subcutaneous tissue necrosis. The patient underwent a plantar medial incision and drainage following hallux amputation. Figure 3. Clinical photograph showing right foot transmetatarsal amputation after 25 days and extracellular matrix dressing to plantar wound after 9 days. 220 May/June 2016 Vol 106 No 3 Journal of the American Podiatric Medical Association

4 Figure 4. Postoperative photograph showing right foot with penrose drain 2 days after transmetatarsal amputation. walker and was discharged from the hospital after a 36-day stay. He was discharged with oral clindamycin, with scheduled follow-up clinic visits. Seen in the podiatric surgery clinic approximately 3 months after presenting to the emergency department, the patient was bearing full weight in a CAM walker. He was being treated in the clinic for Figure 6. Postoperative photograph showing right foot transmetatarsal amputation after 25 days, with extracellular matrix dressing to plantar wound after 9 days. a wound dehiscence along the distal transmetatarsal site, measuring cm and cm at this time. The plantar foot wound measured cm, respectively. He was receiving dressing changes weekly by home health skilled nursing services, with no local signs of Figure 5. Postoperative photograph showing right foot 7 days after transmetatarsal amputation. A, Dorsal view; B, Plantar view. Journal of the American Podiatric Medical Association Vol 106 No 3 May/June

5 Figure 7. Postoperative photograph showing right foot transmetatarsal amputation after 25 days. infection. About 4 months postoperatively, the patient reported to the clinic with evidence of improvement to his wounds. Along the distal surgical site there was a wound measuring cm with a granular base and mild hyperkeratotic border. All other wounds were healed at this time. At his visit 6 weeks later, he was completely healed, with only a small hyperkeratotic lesion noted plantar to the first metatarsal of his right foot (Figs. 8 and 9). The patient initially presented with osteomyelitis to the right hallux suggested by plain radiographs (Fig. 10); the implementation of definitive surgical debridement resulted in a functional limb. He started walking with the use of a custom-molded, extra-depth shoe with a forefoot filler, with no further complications. Currently, he is scheduled for follow-up visits in the podiatric surgery clinic for palliative diabetic foot and nail care. He also expressed an interest in volunteering at the hospital in hopes of educating fellow veterans on the importance of controlling diabetes and becoming proactive with routine foot evaluation. Figure 8. Photograph showing complete healing of right foot transmetatarsal amputation site approximately 5.5 months after initial presentation to the emergency department. When a diabetic foot wound is complicated by a group B and F streptococcus bacterial infection, a prompt decision needs to be made to perform surgical debridement of all nonviable tissue, with Discussion A deep plantar space abscess and a group B beta streptococcus infection may increase the risk of a more proximal amputation. A necrotizing infection may also increase the length of hospital stay, requiring prolonged intravenous antibiotic therapy. Figure 9. Photograph showing completely healed plantar medial incision, with hyperkeratotic lesion noted plantar to first metatarsal approximately 5.5 months after initial presentation to the emergency department. 222 May/June 2016 Vol 106 No 3 Journal of the American Podiatric Medical Association

6 Figure 10. Initial anterioposterior (A), medial oblique (B), and lateral (C) plain radiographs suggestive of bony destruction involving hallux of the right foot. exploration through the three main compartments of the foot. The surgery performed should be aggressive and prompt in order to salvage the limb. The application of advanced healing modalities gives the patient an opportunity to return to activities of daily living sooner by decreasing healing time. A series of extracellular matrix dressing applications were performed to expedite healing to allow for early ambulation. The application of the antibiotic-impregnated beads allows for a local infiltration of antibiotics to the site of infection. A necrotizing infection can occur, requiring a prompt diagnosis, a multi-disciplinary approach and surgical debridement. Acknowledgment: This material is the result of work supported with the resources and the use of facilities at the Southern Arizona VA Health Care System. Financial Disclosure: None reported. Conflict of Interest: None reported. References 1. WANG KC, SHIH CH: Necrotizing fasciitis of the extremities. J Trauma 32: 179, WIPF SA, GREENHAGEN RM, MANDI DM, ET AL: Necrotizing soft tissue infection of the foot: a case report. Foot Ankle J 1: 4, BERNHARD LM, BAKST M, COLEMAN W, ET AL: Plantar abscesses in the diabetic foot: diagnosis and treatment. J Foot Surgery 23: 283, LANCEFIELD RC: A serological differentiation of human and other groups of hemolytic streptococci. J Exp Med 57: 571, GUTHOFF O: Ueber pathogen vergrunende Streptokokken. Streptokokken-Befunde bei dentogenen abszessen und infiltraten im Bereich der Mundhole. Zentralbl Bakteriol Parasitenkd Infectionskr Hyg Abt 1 Orig 166: 553, Journal of the American Podiatric Medical Association Vol 106 No 3 May/June

7 6. LONG PH, BLISS EA: Studies upon minute hemolytic streptococci : I. the isolation and cultural characteristics of minute beta hemolytic streptococci. J Exp Med 60: 619, WHITWORTH JM: Lancefield group F and related streptococci. J Med Microbiol 33: 135, LIBERTIN CR, HERMANS PE, WASHINGTON II JA: Betahemolytic group F Streptococcal bacteremia: a study and review of the literature. Rev Infect Dis 7: 4, RIGHTER J, ZWERVER J: Infections caused by group F streptococci. CMAJ 125: 1008, JUNCKERSTORFF RK, ROBINSON JO, MURRAY RJ: Invasive Streptococcus anginosus group infection-does the species predict the outcome? Int J Infect Dis 18: 38, OGAWA D, SHIKATA K, WADA J, ET AL: Successful treatment of necrotizing fasciitis associated with diabetic nephropathy. Diabetes Res Clin Practice 60: 213, HOLMSTRÖM B, GRIMSLEY EW: Necrotizing fasciitis and toxic shock-like syndrome caused by group B streptococcus. Southern Med J 93: 1096, May/June 2016 Vol 106 No 3 Journal of the American Podiatric Medical Association