Lower-Extremity Infections Caused by Serratia marcescens
A Report of Three Cases and a Literature Review
Serratia marcescens is a ubiquitous, facultatively anaerobic, gram-negative bacillus that has been cited to cause infection in immunocompromised populations. In the literature, S marcescens infections of the lower extremity have presented as granulomatous ulceration, abscess, bullous cellulitis, and necrotizing fasciitis. Herein we present a series of three cases of lower-extremity infections in which S marcescens was the sole or a contributing pathogen. We discuss the commonalities of these three cases as well as with those previously cited. All three patients presented with some combination of a similar set of clinical characteristics, including bullae formation, liquefactive necrosis, and black necrotic eschar. All three patients were diabetic and had peripheral vascular disease.
Osteolysis, caused by active resorption of bone matrix by osteoclasts, can be primary or can develop secondary to a variety of disease processes. An elevated level of inflammatory cytokines in the local milieu and increased blood flow secondary to infection or autonomic neuropathy stimulate the osteoclasts and cause bone loss in the diabetic foot. Charcot's neuroarthropathy and osteomyelitis are well-known foot complications of diabetes, and secondary osteolysis has largely been underappreciated and, hence, underreported. Plain radiographs, an initial component in the evaluation of the diabetic foot, may not successfully differentiate secondary osteolysis from osteomyelitis. We describe a patient with phalangeal osteolysis secondary to soft-tissue infection in whom a correct and timely diagnosis helped avoid unnecessary surgical interventions.
We report a case of an unusual and unsuspected chronic infection creating a soft-tissue mass in the foot of a 35-year-old woman. The causative agent, Mycobacterium gordonae, is usually encountered as a laboratory contaminant. Only rarely does it manifest as a clinical infection. The patient’s presumed predisposing risk factor was a history of barefoot gardening. An iatrogenic source, corticosteroid injections, was also considered. (J Am Podiatr Med Assoc 98(4): 311–313, 2008)
Surgical management of hallux rigidus using a polyvinyl alcohol synthetic cartilage implant has gained popularity among foot and ankle surgeons. Although uncommon, appropriate diagnosis and management of a periprosthetic implant infection is critical in limiting morbidity. We present a case report and staged technique for converting a first metatarsal synthetic cartilage hemiarthroplasty to arthrodesis in the setting of a periprosthetic joint infection.
Hematoma refers to the collection or extravasation of blood, usually clotted, in a closed tissue space. It is caused by leakage from local vessels damaged by blunt trauma, local injury, or surgical dissection. In the postoperative phase, a hematoma often results in edema, pain, wound dehiscence, infection, and scarring of the surgical wound. We describe a 44-year-old woman who developed severe complications, including hematoma, abscess, failure of internal fixation, and loss of soft-tissue structures, after hallux abducto valgus surgery. Hospitalization was required for infection control, soft-tissue coverage through negative-pressure wound therapy, and first metatarsophalangeal joint stabilization through external fixation. Early recognition of the signs of infection and hematoma can help decrease the incidence of postoperative complications. (J Am Podiatr Med Assoc 97(5): 410–414, 2007)
The treating podiatric physician should consider underlying malignant disease when evaluating a child with any slowly healing or nonhealing infection involving the lower extremity. This article reports on an infant who was treated for suspected osteomyelitis involving his right fifth toe that did not improve with standard surgical, medical, and antibiotic treatments. He was later diagnosed as having acute myelogenous leukemia. (J Am Podiatr Med Assoc 97(2): 145–147, 2007)
Gout is a purine metabolism disease. Tophaceous gout may cause joint destruction and other systemic problems and sometimes may be complicated by infection. Infection and sinus with discharge associated with tophaceous gout are serious complications, and treatment is difficult. We present a patient with tophaceous gout complicated by infection and discharging sinus treated by bilateral amputation at the level of the first metatarsus.
A 43-year-old man previously diagnosed as having gout, and noncompliant with treatment, presented with tophaceous gout associated with discharging sinus and infection on his left first metatarsophalangeal joint. Because of the discharging sinus associated with the tophaceous deposits, the soft-tissue and bony defects, and the noncompliance of the patient, amputation of the first ray was undertaken, and a local plantar fasciocutaneous flap was used to close the defect. After 8 months, the patient was admitted to the emergency department with similar symptoms in his right foot, and the same surgical procedure was performed.
One year after the second surgery, the patient had no symptoms, there was no local inflammatory reaction over the surgical areas, and laboratory test results were normal.
Gout disease with small tophi often can be managed conservatively. However, in patients with extensive lesions, risk of superinfection justifies surgical treatment. Results of complicated cases are not without morbidity; therefore, early surgical treatment may prevent extremity loss and further complications. In severe cases, especially with compliance issues, amputation provides acceptable results.
Group B and F Beta Streptococcus Necrotizing Infection–Surgical Challenges with a Deep Central Plantar Space Abscess
A Diabetic Limb Salvage Case Report
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.
Methicillin-Resistant Staphylococcus aureus Endocarditis from a Diabetic Foot Ulcer
Understanding and Mitigating the Risk
Diabetic foot infections are a common cause of morbidity and mortality in the United States, and successful treatment often requires an aggressive and prolonged approach. Recent work has elucidated the importance of appropriate therapy for a given severity of diabetic foot infection, and highlighted the ongoing risk such patients have for subsequent invasive life-threatening infection should diabetic foot ulcers fail to heal. The authors describe the case of a man with diabetes who had prolonged, delayed healing of a diabetic foot ulcer. The ulcer subsequently became infected by methicillin-resistant Staphylococcus aureus (MRSA). The infection was treated conservatively with oral therapy and minimal debridement. Several months later, he experienced MRSA bloodstream infection and complicating endocarditis. The case highlights the ongoing risk faced by patients when diabetic foot ulcers do not heal promptly, and emphasizes the need for aggressive therapy to promote rapid healing and eradication of MRSA.
Immigration Brings New Pathology with No Standardized Treatment Protocol
Madura Foot Case Studies Phialemonium and Phaeoacremonium
Madura foot is an uncommon invasive soft-tissue infection that foot and ankle specialists encounter. We present two rare cases of Phialemonium and Phaeoacremonium fungi infections of the foot diagnosed in northern California to inform physicians on the presentation and current treatment options for this unique pathology. The two cases presented outline the clinical presentations, diagnostic data, and surgical and antimicrobial interventions. There is a concentration on the antimicrobial options depending on which of the over 20 species is encountered. The pertinent literature and supporting data are reviewed to create an outline for discussion of treatment protocols when faced with these emerging opportunistic infections.