Surgical site infections (SSI) of the abdominal wall in renal transplant recipients can on occasion require management with negative pressure wound therapy (NPWT). This is often successful, with a low risk of further complications. However, we describe three cases in which persistent or recurrent surgical site sepsis occurred, whilst NPWT was being deployed in adults with either wound dehiscence or initial SSI. This type of complication in the setting of NPWT has not been previously described in renal transplant recipients. Our case series demonstrates that in immunosuppressed transplant recipients, there may be ineffective microbial or bacterial bioburden clearance associated with the NPWT, which can lead to further infections. Hence recognition for infections in renal transplant patients undergoing treatment with NPWT is vital; furthermore, aggressive management of sepsis control with early debridement, antimicrobial use, and reassessment of the use of wound dressing is necessary to reduce the morbidity associated with surgical site infections and NPWT.
In adult renal transplant recipients, the rate of reported surgical site infections (SSI) varies from 4.8–18.6% [
Negative pressure wound therapy (NPWT), or vacuum assisted closure (VAC) therapy, has become a useful adjunct in the management of wound complications or SSI in orthopedic trauma and general surgery [
At our institution, the standard approach to managing abdominal wall complications after renal transplant detected clinically or radiologically is to drain, debride, and clean the wound at the bedside or in the operating theatre and then apply the NPWT.
All wounds which were suspected to be clinically infected are all initially swabbed and the swabs sent for microscopy, culture, and sensitivities (MCS) analysis. Antimicrobial therapy was given empirically in the setting of acute onset of SSI with evidence of spreading infection, and then tailored according to culture sensitivities or local sensitivity patterns, and was decided on a case by case basis and with infectious disease service input.
Application of the NPWT at our institution involves using black polyurethane foam, which is cut to size and applied to the wound and then sealed using an occlusive dressing at a continuous negative pressure of 125 mmHg connected to an “ActiVac” Therapy system (Vacuum Assisted Closure, VAC Therapy KCI Medical Pty Ltd USA [
A 68-year-old female with a BMI of 34 kg/m2 and a history of polycystic kidney disease, underwent a deceased donor renal transplant in December 2017, with initial graft function being obtained. Three days post-transplant, the recipient developed a serous discharge at the supero-lateral aspect of the wound, secondary to the presence of a subcutaneous abdominal wall collection. The supero-lateral aspect of the hockey stick surgical wound was opened, a microbiology swab taken and sent for MCS, followed by wound irrigation with a copious amount of normal saline along with wound debridement at the bedside until the wound itself was clean, with a healthy intact base. A tapered piece of black foam was placed in the lateral aspect of the surgical wound, and the NPWT was applied at a continuous negative pressure of 125 mmHg, noting that the skin over the infero-medial aspect of the wound remained intact. The microbiology swab grew coagulase negative
The NPWT was continued in the community due to slow wound healing with twice-weekly dressing changes, with the wound initially appearing clean, with a healthy intact wound base, with no other clinical signs of infection during regular surgical team review. However, on day 24 post-transplant, the recipient developed evidence of an additional SSI, with new tenderness to clinical palpation at the inferno-medial aspect of the wound. However, the supero-lateral aspect of the wound base on clinical examination, after removal of the foam, appeared clean. Hence a computed tomography (CT) scan of the abdomen and pelvis was performed, which showed a small subcutaneous collection in the medial aspect of the abdominal wall, but separate to the NPWT foam. This collection was then aspirated percutaneously under ultrasound guidance. The culture of the aspirated fluid revealed a scanty growth of
A 59-year female with a BMI of 30.1 kg/m2 and a background of diabetes and hypertension underwent a deceased donor renal transplant in November 2017. She then had delayed graft function, requiring haemodialysis within the first week. At 19 days post-transplant, the recipient developed a new clinically evident superficial abdominal wall collection above the deep fascia. There were no signs of spreading infection. The wound was re-opened at the bedside, swabbed for MCS, washed out with copious saline irrigation, and debrided until clean, and the wound base was clean and intact with evidence of granulation. The NPWT with black foam was applied at −125 mmHg continuous pressure. This initial wound swab MCS was negative for organisms at this stage. The dressings were changed twice a week, first as an inpatient, and then as an outpatient, the wound appeared to be clean with a healthy base on dressing changes.
However, on day 59 post-transplant, during a routine dressing change, a new collection of turbid fluid was detected beneath the foam, anterior to the deep fascia. This wound appeared infected, with slough at the base; therefore, it required copious washout and debridement in the operating theatre, until the wound base appeared clean and intact and the NPWT was then reapplied. This wound swab MCS revealed a penicillin sensitive
At 79 days post-transplant, the recipient developed urinary sepsis and acute kidney injury along with a concurrent abscess in the abdominal wall, deep to the NPWT foam, which was detected on CT scan of the abdomen and pelvis. The NPWT dressings were immediately removed at the bedside, the wound appeared infected, with abscess and was again swabbed and washed out. The NPWT was abandoned due to recurrent abscess formation around the foam. This was then replaced with a regimen of simple gauze dressings. The wound swab MCS grew
A 55-year female with a BMI of 42.3 kg/m2 and a background of IgA nephropathy underwent a deceased donor renal transplant in January 2017. She had a spontaneous fall in serum creatinine within 72 h, and was initially making an uncomplicated recovery. However, when lower abdominal symptoms developed, a deep fascial dehiscence along with a superficial fluid collection was detected clinically and then confirmed with CT imaging of the abdomen and pelvis. This required surgical debridement and operative repair on post-transplant day 20. The abdominal fluid collection appeared turbid and was swabbed for MCS, furthermore deep fascial closure was not possible due to a combination of tissue oedema and tissue loss. Therefore, a tension free repair with a dual layer vicryl and prolene onlay mesh was performed and the skin was closed primarily with interrupted nylon sutures. The abdominal wall culture was positive for
On post-transplant day 59, the recipient developed a new serous discharge from the skin at the surgical site, secondary to a clinically detected superficial collection. This required reoperative surgery with a thorough wash out; unhealthy tissue within the wound was debrided until the tissue at the wound base was clean and intact. The NPWT dressing was applied, with black foam at continuous pressure of −125 mmHg, to the surgical site. A repeat wound swab performed intraoperatively revealed scanty growth of
Five days following the NPWT removal, the recipient re-presented with new clinical signs of sepsis, and an urgent CT scan confirmed an abscess within the subcutaneous tissue of the surgical site. This required operative management, and the superficial wound was reopened, swabbed, and unhealthy, devitalized tissue was debrided along with a copious wash out being performed. Of note, the prosthetic mesh had healed into the deep abdominal wall; hence, the foam and NPWT were reapplied superficial to the mesh. This was tolerated well. The recipient received intravenous Tazocin, and was stepped down to oral amoxicillin and clavulanic acid combined with metronidazole and fluconazole for 3 weeks. The wound MCS on delayed tissue culture on enrichment growth revealed a
We report three cases of renal transplant recipients who despite being managed in a standard manner with a NPWT dressing regimen for abdominal wall complications, have then all gone on to either develop recurrent infection and or further episodes of sepsis in the abdominal wall, with at times different organisms being involved. This particular complication has not been previously described in the literature, in the context of NPWT being used to manage a spectrum of abdominal wall surgical site complications in renal transplant recipients [
Up to now NPWT has been used successfully to manage contaminated or infected wounds with generally minimal complications [
Although the mechanisms associated with the onset of infectious complications with the use of NPWT in our cases are not totally clear, the immunosuppressed state of renal transplant recipients may predispose them to developing further sepsis, particularly in the setting of persistent microbial colonisation of the wound, which can occur despite the use of NWPT [
Our three cases who were all transplanted with allografts from deceased donors, sustained further infectious complications associated with a range of organisms including
One of the possible risks for the development of SSI with NPWT is that the polyurethane foam acts as a foreign body, generating an inflammatory reaction in the wound [
Obesity is a known risk factor for abdominal wall complications in renal transplant recipients [
This case report is beneficial in highlighting the unusual complication of further SSI that may be associated with the use of NPWT dressings in renal transplant recipients and the prolonged time then taken to achieve full healing of the abdominal wall. This can add to the significant challenges associated with managing ongoing abdominal wall complications in the context of obesity, immunosuppression, and prolonged wound healing. The potential for this additional complication also necessitates that clinical vigilance be maintained for adult recipients in whom NPWT is being utilized. Furthermore, we highlight the need to tailor the management approach to each patient, by using a combination of bedside management, radiological, and surgical approaches, as required.
We also highlight the added financial cost and burden of managing ongoing surgical site infection with the ensuing requirement for prolonged wound management for periods of up to 180 days requiring further procedures in hospital, along with further use of the NPWT and or, other dressings. Use of the NPWT device with two foam dressing changes costs up to $AUD 500 per week, or approximately $AUD 7,000 for the average NPWT usage of 102 days for the device consumables, in addition to the cost of staff time spent on managing the dressings and performing procedures, the cost of additional antibiotics plus the extra in-hospital stay costs. However, being able to deliver NPWT as an outpatient can save on additional inpatient costs. This was an approach utilised in all three of our cases, as previously described in a group of patients with complex abdominal wall surgical site issues following general surgical procedures [
This case report is limited by the small sample size and its retrospective nature. There is also potential for false positives in wound culture, although wounds were reviewed regularly for signs of infection and managed based on clinical findings. The true effect of NPWT and the associated risk of complications related to its use in renal transplant recipients will require further collaborative prospective studies. It is apparent that the use of NPWT may not clear a wound of bacterial contamination, and there is an ongoing risk of further bacterial proliferation and possible infection in the context of NPWT [
The management of surgical site infections and wound breakdown in adult renal transplant recipients is challenging. The use of NPWT can often successfully promote wound healing of the open abdominal wall in this particular cohort. However, our case series demonstrates that in immunosuppressed transplant recipients, there may be ineffective microbial or bacterial bioburden clearance associated with the NPWT and antimicrobial use, which can lead to further infections ensuing. As such, when an infection is detected, we recommend sepsis control with antimicrobial therapy in conjunction with early and aggressive surgical debridement for control of sepsis and reassessment of the dressing strategy, which may or may not involve further use of NPWT.
Australian dollars
Body mass index
Computed tomography
Microscopy culture sensitivities
Negative pressure wound therapy
Surgical site infection
Vacuum assisted closure.
All patients have provided informed consent for inclusion of their case in this case report.
The authors declare that they have no conflicts of interest.