Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 2399
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size

  Table of Contents    
Year : 2012  |  Volume : 55  |  Issue : 3  |  Page : 386-388
Pantoea agglomerans infection behaving like a tumor after plant thorn injury: An unusual presentation

1 Department of Microbiology and Orthopedics, All India Institute of Medical Sciences, New Delhi, India
2 BLK Super Speciality Hospital, Pusa Road, New Delhi, India
3 Department of Pathology, All India Institute of Medical Sciences, New Delhi, India

Click here for correspondence address and email

Date of Web Publication29-Sep-2012


Pantoea agglomerans infections in humans are uncommon. Most common infections reported are septic arthritis or synovitis. We report the case of a 25-year-old, healthy male, who presented with indurated swelling over the posterolateral aspect of his right thigh, associated with pain for one month. Magnetic resonance imaging (MRI) revealed muscle edema with cystic areas in the posterior-most part of the vastus lateralis of the right thigh. The condition was clinically diagnosed as a right-sided benign tumor of the vastus lateralis muscle. However, Pantoea agglomerans was isolated on a culture of the excised muscle tissue. On the basis of the awareness of the common association of Pantoea with penetrating trauma by vegetation, the patient was asked to recollect any prior such injury. He then gave a history of a fall in the field and a plant thorn prick in the thigh four years back, when he was an agricultural worker. We emphasize the importance of Pantoea agglomerans infection of the soft tissues that can have an atypical presentation as a non-suppurative, indurated, muscle cyst in our case. Thorn injuries are usually ignored as trivial incidents, however, Pantoea infections should always be borne in mind when encountering soft tissue lesions, as antibiotic treatment is required for complete resolution of the lesion.

Keywords: Pantoea agglomerans , thorn injury, muscle cyst

How to cite this article:
Jain S, Bohra I, Mahajan R, Jain S, Chugh T D. Pantoea agglomerans infection behaving like a tumor after plant thorn injury: An unusual presentation. Indian J Pathol Microbiol 2012;55:386-8

How to cite this URL:
Jain S, Bohra I, Mahajan R, Jain S, Chugh T D. Pantoea agglomerans infection behaving like a tumor after plant thorn injury: An unusual presentation. Indian J Pathol Microbiol [serial online] 2012 [cited 2022 Jun 27];55:386-8. Available from: https://www.ijpmonline.org/text.asp?2012/55/3/386/101754

   Introduction Top

Bacterial infections after plant thorn injury are rarely reported. Pantoea agglomerans is reported as the most common organism isolated after such injuries, in the scarce reports available worldwide. [1] Pantoea infections are uncommon in humans. Within the genus Pantoea, the most prominent species and most common hospital isolate is P. agglomerans (formerly named Enterobacter agglomerans). Pantoea agglomerans is a gram-negative aerobic bacilli member of the Enterobacteriaceae family, commonly found in plants, soil, and feces of humans and animals, being primarily an environmental and agricultural organism. [1] The most common clinical presentation described is acute synovitis followed by chronic inflammation mimicking septic arthritis, osteomyelitis or bone tumor following penetrating trauma by vegetation. [2] Rarely, have systemic infections been described as nosocomial outbreaks. [3] We present a case of Pantoea agglomerans, isolated from a plant thorn induced non-suppurative muscle cyst.

   Case Report Top

A twenty-five-year old, healthy male presented to the Outpatient Department with localized swelling and pain over the right thigh. The pain and swelling appeared one month back and due to gradually increasing pain, his movements were restricted. There was no accompanying fever. The patient denied any history of recent trauma. No history of contact with a case of tuberculosis was present. His general physical examination was normal. On local examination, a 2 × 2 cm-sized swelling was present, with induration and marked tenderness over the posterolateral aspect of the right thigh. A plain radiograph showed a normal impression, with no evidence of periosteal reaction or synovitis. Magnetic resonance imaging revealed muscle edema, with cystic areas in the posterior most part of vastus lateralis at the level of the junction of the middle and lower one-third of the thigh, with subcutaneous edema of the overlying skin. Clinical diagnosis of a right-sided benign tumor of vastus lateralis muscle was made. Fasciotomy and excisional biopsy of the mass was performed followed by a thorough debridement. An intraoperative muscle tissue specimen was sent for culture and histopathological examination. Postoperatively, the patient was started on cefuroxime therapy and was discharged in a stable condition.

Histopathological examination showed foreign body granuloma with many giant cells [Figure 1]. In the microbiology laboratory, the tissue received for culture was cut into small pieces with a sterile scissor and ground into a homogeneous suspension. The suspension was inoculated in a brain-heart infusion broth, for enrichment, and directly on blood agar and MacConkey agar. On subculture from the broth, after 24 hours, lactose fermenting colonies were obtained, which were identified as Pantoea agglomerans by Phoenix 100, an automated microbiology system (BD, USA). Antimicrobial susceptibility testing showed the isolate was sensitive to amikacin (MIC: ≤ 8 mcg / ml), cefepime (MIC: = 8 mcg / ml), ceftriaxone (MIC: ≤ 2 mcg / ml), levofloxacin (MIC: ≤ 1 mcg / ml), piperacillin-tazobactum (MIC: = 16 / 4 mcg / ml), meropenam (MIC: ≤ 1 mcg / ml), and amoxicillin-clavulanate (MIC: = 8 / 4 mcg / ml); and resistant to ceftazidime (MIC: > 16 mcg / ml), ciprofloxacin (MIC: > 2 mcg / ml), aztreonam (MIC: > 16 mcg / ml), and imepenam (MIC: > 4 mcg / ml).
Figure 1: Histopathogical examination of tissue showing foreign body granuloma with many giant cells (H and E, ×400)

Click here to view

On a postoperative follow-up visit of the patient, after five days, the antibiotic therapy was changed to levofloxacin for one week according to the antibiotic susceptibility report. On the basis of the culture report, his medical history was detailed and was again asked for any recent or remote history of injury to the thigh. He could recollect a minor plant thorn prick injury to the thigh about four years back, after he had a fall in his farm, when he was an agricultural worker. Thereafter, he had changed his occupation and had completely forgotten the incident.

On a subsequent postoperative visit after two weeks, the lesion was clinically healthy and patient had resumed his normal daily movements.

   Discussion Top

Pantoea agglomerans (formerly named Enterobacter agglomerans) is a gram-negative aerobic bacilli member of the Enterobacteriaceae family, commonly found in plants, soil, and feces of humans and animals, being primarily an environmental and agricultural organism. Infections by P. agglomerans are usually associated with an identifiable exogenous source. Most commonly, it causes septic arthritis or synovitis, following a penetrating injury by vegetation. [1] Few cases of sepsis, [4] cholelithiasis, [5] peritonitis, [6] occupational respiratory diseases, [7] endophthalmitis, [8] and abscess [4] have also been described. Organic materials in the form of plant thorns may penetrate the skin, remain embedded in the tissues, and set up a chronic inflammatory response. The cases of Pantoea infection after thorn injury reported so far, describe lesions of bones / joints and periarticular soft tissues. The finding of non-suppurative, indurated soft tissue (muscle) cystic swelling, in association with plant thorn-induced Pantoea agglomerans infection is quite unusual. Fortunately, the inflammatory response was confined to the muscles of the thigh of our patient and did not involve the deeper anatomical structures.

Correct diagnosis and treatment are delayed as these vegetable matters are not visualized on plain radiographs and non-specific findings on a CT scan may be misinterpreted. Occasionally, small thorn particles may be visualized on an ultrasound or MRI scan, but may be easily missed. Foreign body retention may lead to development of symptomatic lesions, ranging from weeks to many years after the injury, by which time the patient would have forgotten the specific injury event. [9] Histopathological examination usually demonstrates a granulomatous reaction and should raise a suspicion of foreign body retention. In our case, muscle cystic mass was thought to be a benign tumor clinically and was removed through excisional biopsy and sent for culture and histopathological examination. The latter report suggested features of tuberculosis, based on the presence of granulomatous inflammation. However, on culture, isolation of Pantoea agglomerans raised the suspicion of prior thorn injury to the patient, which was confirmed on his postoperative follow-up visit to the hospital. He could recall a plant thorn prick to the thigh after a fall in his own farmland, about four years back, when he was an agricultural worker.

The awareness of the association of Pantoea agglomerans with thorn injuries helped in arriving at the diagnosis of thorn-induced soft tissue cystic swelling. Young men who spend a significant time of their day outdoors are highly susceptible to plant-associated trauma, particularly those involved in occupations prone to such accidents. After an extensive review of literature, to our knowledge, there is no case reported so far of Pantoea-associated muscle cyst development. Thus, the case is presented to illustrate the unusual manifestation of Pantoea agglomerans infection and the challenges presented to clinicians when diagnosing such cases.

   References Top

1.Kratz A, Greenberg D, Barki Y, Cohen E, Lifshitz M. Pantoea agglomerans as a cause of septic arthritis after palm tree thorn injury; case report and literature review. Arch Dis Child 2003;88:542-4.  Back to cited text no. 1
2.Balasubramaniam P, Pratap K. Pseudotumors due to oil palm thorn injury. Aust N Z J Surg 1977;47:223-5.  Back to cited text no. 2
3.Habsah H, Zeehaida M, Van Rostenberghe H, Noraida R, Wan Pauzi WI, Fatimah I, et al. An outbreak of Pantoea spp. in a neonatal intensive care unit secondary to contaminated parenteral nutrition. J Hosp Infect 2005;61:213-8.  Back to cited text no. 3
4.Cruz AT, Cazacu AC, Allen CH. Pantoea agglomerans, a plant pathogen causing human disease. J Clin Microbiol 2007;45:1989-92.  Back to cited text no. 4
5.Flores C, Maguilnik I, Hadlich E, Goldani LZ. Microbiology of choledochal bile in patients with choledocholithiasis admitted to a tertiary hospital. J Gastroenterol Hepatol 2003;18:333-6.  Back to cited text no. 5
6.Lim PS, Chen SL, Tsai CY, Pai MA. Pantoea peritonitis in a patient receiving chronic ambulatory peritoneal dialysis. Nephrology (Carlton) 2006;11:97-9.  Back to cited text no. 6
7.Milanowski J, Dutkiewicz J, Potoczna H, Ku? L, Urbanowicz B. Allergic alveolitis among agricultural workers in eastern Poland: A study of twenty cases. Ann Agric Environ Med 1998;5:31-43.  Back to cited text no. 7
8.Lee NE, Chung IY, Park JM. A Case of Pantoea endophthalmitis. Korean J Ophthalmol 2010;24:318-21.  Back to cited text no. 8
9.Reginato AJ, Ferreiro JL, O'Connor CR, Barbasan C, Arasa J, Bednar J, et al. Clinical and pathologic studies of twenty-six patients with penetrating foreign body injury to the joints, bursae, and tendon sheaths. Arthritis Rheum 1990;33:1753-62.  Back to cited text no. 9

Correspondence Address:
Sarika Jain
Department of Microbiology, BLK Super Speciality Hospital, Pusa Road, New Delhi - 110005
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0377-4929.101754

Rights and Permissions


  [Figure 1]

This article has been cited by
1 Bacterial infective stifle arthritis secondary to a migrating grass seed foreign body in an adult dog
Sebastian Prior, Gareth Arthurs
Veterinary Record Case Reports. 2021; 9(3)
[Pubmed] | [DOI]
2 Coastal Ecosystems as Sources of Biofertilizers in Agriculture: From Genomics to Application in an Urban Orchard
Eloísa Pajuelo, Sandra Arjona, Ignacio D. Rodríguez-Llorente, Enrique Mateos-Naranjo, Susana Redondo-Gómez, Francisco Merchán, Salvadora Navarro-Torre
Frontiers in Marine Science. 2021; 8
[Pubmed] | [DOI]
3 Septic arthritis of the knee due to <i>Pantoea</i> <i>agglomerans</i>: look for the thorn
Tobias Koester, Taro Kusano, Henk Eijer, Robert Escher, Gabriel Waldegg
Journal of Bone and Joint Infection. 2020; 6(3): 51
[Pubmed] | [DOI]
4 Prospective study of blackthorn injury and synovitis in 35 horses
N. M. Ashton
Equine Veterinary Education. 2018;
[Pubmed] | [DOI]
5 Sinovitis por cuerpo extraño punzante
E. Palazzo
EMC - Aparato Locomotor. 2017; 50(2): 1
[Pubmed] | [DOI]
6 Culture-Proven Thorn-Associated Infections in Arizona: 10-Year Experience at Mayo Clinic
Sierra C. Simmons,Adriane I. Budavari,Shimon Kusne,Nan Zhang,Holenarasipur R. Vikram,Janis E. Blair
Open Forum Infectious Diseases. 2017; 4(1)
[Pubmed] | [DOI]
7 Pantoea agglomerans - an underestimated pathogenic agent in penetrating trauma involving vegetative material
F. Friedling,A.S. Kekulé,W. Ch. Marsch,V. Stadie
Journal of the European Academy of Dermatology and Venereology. 2015; : n/a
[Pubmed] | [DOI]
8 Pantoea species causing early onset neonatal sepsis: a case report
Shreekant Tiwari,Siba Shankar Beriha
Journal of Medical Case Reports. 2015; 9(1)
[Pubmed] | [DOI]
9 Non-pathogenic microflora of a spring water with regenerative properties
Biomedical Reports. 2015; 3(6): 758
[Pubmed] | [DOI]
10 Synovites à piquants : à propos de deux cas
E. Fianyo,S. Guignard,A. Economu,N. Thellier,K. Davidowicz,X. Chevalier
La Revue de Médecine Interne. 2015; 36(6): 426
[Pubmed] | [DOI]
11 Plant thorn synovitis of elbow in children
Ajay Bharti,Kriti Mohan,Snajay Kumar,Vineet Kumar
Journal of Clinical Orthopaedics and Trauma. 2014;
[Pubmed] | [DOI]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Email Alert *
    Add to My List *
* Registration required (free)  

   Case Report
    Article Figures

 Article Access Statistics
    PDF Downloaded98    
    Comments [Add]    
    Cited by others 11    

Recommend this journal