Ann Thorac Surg 1996;61:1646-1650
© 1996 The Society of Thoracic Surgeons
Original Article: General Thoracic
Pneumothorax and Wound Dehiscence Related to Collagenase Deregulation: Treatment With Diphenylhydantoin
Michael J. O'Toole, BA,
James E. Kolb, MD,
William J. Lindblad, PhD,
I. Kelman Cohen, MD,
Martin F. McKneally, MD, PhD
Departments of Surgery and Medicine, Albany Medical College, Albany, New York, and Department of Plastic and Reconstructive Surgery, Medical College of Virginia, Richmond, Virginia
Accepted for publication March 8, 1996.
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Abstract
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Background. Wound dehiscence is an uncommon complication of operation, usually related to a recognized risk factor. A clinical dilemma arises when dehiscence has no identifiable cause or treatment.
Methods. We describe the case of a previously healthy 45-year-old man in whom recurrent spontaneous pneumothoraces developed followed by multiple dehiscences of thoracotomy, diaphragmatic, and abdominal wounds. Analysis over several years of laboratory investigation of cultured tissue from test incisions was initially unsuccessful. The patient was supported symptomatically until a remarkable laboratory finding enabled us to develop an effective treatment plan.
Results. Cultured patient fibroblasts were ultimately found to express abnormally elevated levels of collagenase, which could be inhibited by diphenylhydantoin (phenytoin) in vitro. Treatment of the patient with a course of diphenylhydantoin allowed adequate healing of test incisions and subsequent definitive surgical treatment with successful wound healing.
Conclusions. This report of the rigorous application of the scientific method to the investigation and treatment of an enigmatic case of wound dehiscence might serve as a guide to surgeons faced with similar healing problems.
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Introduction
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Wound healing is a complex process of cell proliferation and collagen synthesis, deposition, cross-linking, degradation, and maturation. Failure of the scar to develop properly may relate to structurally flawed collagen, abnormal cross-linking, or excessive degradative processes. Commonly cited factors associated with failure and disruption include hypoproteinemia, tension, chronic pulmonary disease, advanced age, radiation, vitamin deficiency, anticoagulants, glucocorticoids, and systemic disease including cancer, uremia, infection, jaundice, anemia, and diabetes mellitus [1]. Disruption from these causes usually occurs within 2 weeks of operation. Late dehiscence has been described in patients with connective tissue diseases, including the Ehlers-Danlos syndrome [2].
We identified an abnormality of collagenase secretion from the fibroblasts of a patient with recurring pneumothoraces and late wound dehiscences. Fibroblastic collagenase is the specific and rate-limiting protease required for collagen turnover and remodeling [3, 4]. Eisenberg and associates [5] and Bauer and colleagues [6] found that the anticonvulsant drug diphenylhydantoin (DPH) can inhibit collagenase activity in vitro and reduce blistering in some patients with abnormal dermal collagenase activity related to recessive dystrophic epidermolysis bullosa. Based on their experience, we attempted to reverse our patient's abnormality using DPH.
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Material and Methods
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In April 1983 a 45-year-old white male engineer had a spontaneous left pneumothorax. He had been well, with no history of abnormal healing of minor lacerations and no history of operation. Chest tube insertion at his local community hospital was complicated by hemothorax. A left thoracotomy with ligation of bleeding intercostal vessels and apical bullectomy was performed. He was discharged on the eighth postoperative day after uneventful recovery. Three weeks later the thoracotomy scar began to separate. At 8 weeks, dehiscence of deep fascia, serratus anterior, and latissimus dorsi muscles was apparent, covered only by a thin layer of intact epithelium. An incisional hematoma was drained and the wound was reapproximated under general anesthesia. A hematologic evaluation revealed no bleeding diathesis. Pneumothorax recurred and the wound dehisced just as it had before.
After multiple recurrent pneumothoraces, the patient was transferred to the Albany Medical Center in October 1983 for urgent treatment. An emergency laparotomy was performed on arrival, revealing laceration of the diaphragm and spleen secondary to subpulmonary placement of a trocar chest catheter. No adhesions were evident in the abdomen or left chest. Recovery was uneventful and the patient was discharged on the 13th postoperative day with a healed abdominal wound.
Over the next 3 months, a large abdominal incisional hernia evolved beneath a nearly transparent scar. This was repaired with a mesh prosthesis; adhesions were again noted to be absent. A spontaneous right pneumothorax was managed with closed tube thoracostomy. The abdominal scar subsequently dehisced. In August 1984, bilateral spontaneous pneumothoraces occurred during pulmonary function testing. Chest tubes were inserted and pleurodesis was attempted with tetracycline, then with cryoprecipitate and thrombin, without success. Bilateral Foley catheters were attached to Heimlich valves for chronic management of the pneumothoraces while surgical intervention was deferred pending better understanding of the underlying problem.
Past medical history included chronic obstructive pulmonary disease with both restrictive and obstructive components, a 60 pack-year cigarette smoking history, microscopic hematuria, cephalosporin allergy, and acne conglobata of the face and neck. There was no history of diabetes mellitus, Cushing's disease, or intake of exogenous steroids or of penicillamine. Medications included opiate-based analgesics and vitamin C. The patient had no surgical history but reported normal healing of small lacerations of the hands and scalp. The patient's father had a normal appendectomy scar and his mother a normal cholecystectomy scar. A sister and 3 children had no known wound healing problems, and no family members had loose joints, loose skin, or easy bruisability. The patient worked on a road crew for 3 years in the late 1960s, where he was exposed to chemical defoliants, and he was frequently exposed to chemical developers in his own darkroom as an amateur photographer.
The vital signs and body habitus were normal. There were no features of Cushing's or Ehlers-Danlos syndromes. Acne conglobata scars were present on the neck and face. There were decreased breath sounds in both lung fields with no bronchospasm. One or more chest tubes were in place throughout most of his course of illness and treatment. Cardiac examination was unremarkable. There was no arachnodactyly, arthritis, digital clubbing, cyanosis, or edema. Joint mobility and skin elasticity were normal. No pathologic bruises were seen. Paper-thin, translucent epidermal scars on the left thorax (Fig 1
) and abdomen were sharply delineated by normal dermis at the wound edges. The underlying fascia and muscle were dehisced, with lung parenchyma easily palpable beneath the thoracotomy scar through intact skin.
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Fig 1. . Abnormal thoracotomy scar of the patient's left chest wall before the institution of diphenylhydantoin administration.
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Laboratory data included a normal electrocardiogram. The white blood cell count was 10,600/µL, the hemoglobin level was 14.1 g/dL, and the platelet count was 404,000/µL. The prothrombin time, partial thromboplastin time, and levels of electrolytes, urea nitrogen, creatinine, total protein, albumin, calcium, phosphorous, bilirubin, creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and alkaline phosphatase were all within normal limits. Multiple glucose determinations were normal. The 
-glutamyl transferase level was slightly elevated at 85 IU/L (normal, 0 to 65 IU/L). A rheumatoid factor and antinuclear antibody test results were negative. Serum complement was normal. The urine was remarkable for 5 white blood cells and 10 red blood cells per high-powered field, with no casts or protein. Multiple specimens of arterial blood were more than 90% saturated. Other biological determinations were similarly noncontributory. The chest radiograph showed bilateral pneumothoraces and progressive herniation of bowel into the left chest through a dehisced diaphragmatic repair (Fig 2).
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Fig 2. . Chest radiograph before the initiation of diphenylhydantoin administration and surgical reconstruction.
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The initial surgical treatment on the thoracic service at Albany Medical Center consisted of chest tube placement and a 5-cm skin incision for the study of the course of wound healing and harvest of fibroblasts. Foley catheters were placed in the pleural spaces and maintained from August 1984 to November 1985 (15 months) and from January 1986 to December 1986 (11 months). The tubes were dressed daily at home by the patient's wife and changed monthly in the thoracic surgery clinic. Heimlich valves attached to the tubing were irrigated daily with dilute heparin solution, and air was pumped from their outlets when necessary by the patient using a bulb-activated gasoline siphon, a system of his own design. The patient required nasal oxygen for vigorous activity from September 1984 through October 1986.
Analysis of the patient's tissues was extensive, conducted over a 2-year period at four surgical research laboratories. Details of this work, the most significant of which was conducted at the Medical College of Virginia, were recently published by Lindblad and associates [7]. Briefly, tissue biopsy specimens taken from normal skin as well as sites of dehiscence were assessed under light and electron microscopy. Collagen was typed by electrophoresis. Cultures of fibroblasts were isolated and grown in a monolayer. Collagenase activity within the monolayer was measured at rest and after incision of the cultured monolayer, a proliferative signal. This was repeated on the patient's cells and control cultures after exposure to DPH at varying levels.
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Results
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Careful examination of the patient by a geneticist, two rheumatologists, a dermatologist, and multiple internists failed to demonstrate any of the clinical features typical of the Ehlers-Danlos syndrome. Extensive laboratory testing failed to reveal biochemical abnormalities previously associated with abnormal wound healing. Standard small full-thickness test incisions of the skin performed at intervals on the flank provided cells for culture and allowed reassessment of the status of the patient's ability to heal after various empiric manipulations such as change of diet, separation from the home environment, and vitamin supplementation. The incisions always healed primarily and then dehisced after 4 to 5 weeks, leaving a transparent layer of epithelium intact.
The dermis from the biopsy of normal-appearing skin showed a clear definition of papillary and reticular regions containing collagen bundles that were slightly smaller than expected for a normal adult and normal-appearing elastic fibers. The most notable structural findings in the skin were an apparent abundance of diffuse extracellular matrix and thickening of the basement membranes.
In contrast, the dermal scar tissue showed no distinction between papillary and reticular regions, and collagen fiber bundles throughout the scar were uniformly and significantly smaller than those of the normal tissue. Individual collagen fibrils were 50% or less the diameter of the normal fibrils. Elastic fibers were barely visible. In higher magnification electron micrographs they were identified as microfibrillar bundles that contained a sparse amount of elastin matrix. The scar tissue included a high density of cells, primarily inflammatory cells, macrophages, fibroblasts, and plasma cells, within the connective tissue. Collagen typing indicated a normal profile.
Forty-two months after his initial pneumothorax, baseline collagenase activity in the patient's fibroblasts was measured and found to be approximately 20-fold higher than controls. Stimulation of cellular proliferation resulted in a sixfold increase in enzyme released from control cells but no increase in release from the patient's cells. In an attempt to inhibit collagenase secretion, we assayed the patient's cells and control cells in increasing concentrations of DPH. The patient's cells demonstrated concentration-dependent suppression of collagenase activity: all enzymatic activity was abolished at a level of 10 µg/mL. Control cells demonstrated no diminution of enzymatic activity with the addition of DPH (Fig 3).
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Fig 3. . Diphenylhydantoin (DPH) blocks the release of collagenase activity from proliferating patient fibroblasts: a progressive dose response effect is evident. Similar results were obtained when nonproliferating cultures were used. Values in brackets represent mean ± standard deviation, n = 3 (control, shaded bars) or ± range, n = 2 (patient, white bars).
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The demonstration of abnormal collagenase activity and subsequent inhibition in vitro with DPH at the Plastic Surgery Research Laboratory, Medical College of Virginia, came very late in the course of the patient's illness, approximately 3
years after its onset. Based on the in vitro studies of collagenase suppression in his fibroblasts a therapeutic trial of DPH was instituted in October 1986. Serum levels from 15 to 22 µg/mL were maintained throughout the experimental period. Another small test incision was made on the left flank and allowed to heal. The scar maintained a morphologically normal appearance for an unprecedented 6 weeks after incision, convincing us that reconstruction of the chest wall and diaphragm could achieve a durable result. By this time the patient was chronically retaining CO2 and had become progressively more somnolent. He was admitted to the hospital, electively ventilated, and treated for an intercurrent pneumonitis, then taken to the operating room for repair of the defects.
No adhesions were present within the thorax. Several bullae were excised and oversewn. The diaphragm and chest wall were repaired using Marlex mesh (Daval, Inc, Providence, RI). The patient made an uncomplicated recovery from the operation. Postoperatively DPH treatment was maintained at serum levels of 15 to 22 µg/mL. Side effects included mild ataxia and moderate elevations of -glutamyl transferase and alkaline phosphatase levels. During follow-up no new pneumothorax developed and the left thoracotomy scar appeared to heal normally (Fig 4).
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Fig 4. . Thoracotomy revision 11 months after surgical reconstruction. The patient was maintained on a regimen of diphenylhydantoin at minimum serum concentrations of 10 µg/dL.
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Diphenylhydantoin therapy was discontinued after 14 months because of side effects. A small, new diaphragmatic hernia developed gradually. Administration of DPH was resumed and maintained at therapeutic levels for 2 months before the repair was attempted. At thoracotomy in June 1988 the left hemithorax contained dense fibrous adhesions and the previous diaphragmatic repair appeared intact. A new silver dollar-sized rent in the native diaphragm near the previous injury was repaired without incident, and the wound healed normally.
An important but poorly understood development during DPH therapy was gradual loss of vision associated with high titers of antiretinal antibodies. This is not a reported side effect of the medication and remains unexplained. In an attempt to reverse this process, the patient received a 4-week course of plasmapheresis and 14 weeks of prednisone. Although antiretinal antibody titers were reduced, no clinical improvement was demonstrated and immunosuppressive therapy was discontinued. During this period he was also treated with a 20-week course of isotretinoin for severe symptomatic acne conglobata of the face and neck. None of these medications had any apparent effect on his wound healing.
The patient ultimately lost his vision. The exact cause of his death in 1992, six years after his definitive repair, is unknown. Congestive heart failure kept him in a wheelchair for most of his last year of life. Despite blindness he remained active up to that time, working and attending graduate school. He died at a distant site, and no postmortem examination was performed. His family physician thought that he did not have clinical evidence of malignancy but suffered from progressive congestive heart failure. The patient suffered no further wound dehiscences, and to the present, no such problem has developed in any of his 3 children.
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Comment
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There are many instructive elements in this case. The first lesson is the importance of stepping back and reassessing the situation when competent surgical treatment fails. The second is the value of collaborative effort across institutional and interdisciplinary lines. The third is the value of persistence, illustrated by resolution of the problem after 42 months of repeatedly replenished cultures of the patient's cells.
In contrast to the Ehlers-Danlos syndrome, which is a phenotypic manifestation of heritable errors in the production of one of the molecular species of collagen, this patient's wound healing problem probably resulted from a mutation in the genetic control of collagenase. This wound healing defect was too widespread and enduring in his tissues to be attributable to an acquired disorder. The problem was inherent in every fibroblast culture studied and every surgical wound. The mutation was most likely in germline DNA. There is no certainty about the nature or mechanism of its inheritance without more information from an extensive pedigree. We know only that no one else in the patient's immediate family has been similarly affected. The fact that the function of an enzyme is altered raises the likelihood that the mutation involves an autosomal recessive allele. We do know that his Italian parents were not from the same small town in Italy, a circumstance that might strengthen the hypothesis that their son inherited from each parent a rare mutant allele of an autosomal recessive gene. The enzyme itself, an inhibitor, or another control mechanism may have been genetically altered. The late manifestation of the mutation, more common with autosomal dominant disorders, may be attributable in this case to an increased ratio of degradative to synthetic processes with aging, the selective accumulation of an enzyme over time, or the absence of an adequate stimulus like operation. We favor the last hypothesis because of the analogy to heritable disorders like hemophilia or Christmas disease. Although congenital, these mutations may not become evident until late in adult life when the patient is subjected to operation [8]. Although the genetic mechanism remains to be defined, we know that collagenase activity was increased, an important insight that proved clinically helpful to this patient. In retrospect, the importance of collagen remodeling rather than primary scar formation was implicit in the timing of dehiscence, which always occurred late in the healing process, at the fourth to sixth week.
Once deregulated collagenase was identified, we investigated DPH treatment on the basis of reports of its efficacy in inhibiting the enzyme in recessive dystrophic epidermolysis bullosa. First the drug was determined to be effective in the patient's cultured fibroblasts, then it was tested in the patient. There are reports of treatment with DPH to promote healing of various tissues from the time gingival hyperplasia was reported as a side effect of its use as an antiseizure medication. Diphenylhydantoin has been used to promote healing in periodontal disease [9], leg ulcers [10], burns [11], and abscess cavities [12]. In this patient with pneumothorax and wound dehiscence, our experience is provocative but nonspecific. Pneumothorax was certainly a dominant feature of his illness, and is a reported complication of Ehlers-Danlos syndrome, in which collagen is structurally defective, rather than excessively digested during remodeling. The evidence that this patient's pneumothoraces were controlled in part by DPH was clinically convincing. Collagenase inhibition may have therapeutic applications in pneumothorax and emphysema. The drug has many effects on connective tissue. The most relevant to our patient are increased bulk of dense collagen fibers [13] and decreased synthesis and release of collagenase observed in fibroblast cultures treated with DPH [14].
The answer to this patient's wound healing problem did not lie within the realm of usual and common solutions. It was finally derived by rigorous application of the scientific method: the problem was encountered and systematically investigated, a likely etiology was uncovered, a hypothesis was formed and tested in vitro, and the treatment was applied to the patient, with improvement. This simple model is the paradigm of surgical research [15]; application here provided caregivers and researchers with the satisfaction of an answer, and the patient with a finite cure. We have not answered all of the questions posed by this patient, but future students of wound healing, pneumothorax, and emphysema can build on our experience.
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Acknowledgments
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We acknowledge with gratitude the significant contributions of F. C. and Dale Guerra, and of Karen A. Holbrook, PhD, James G. Hoehn, MD, Louise C. Flood, MSc, Timothy Judge, BS, Claude R. Roland, MD, Peter Byers, MD, and Peter Neligan, MD, and an extensive collaborative network of clinical and laboratory personnel, to the description, analysis, and partial solution of this unusual problem.
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Footnotes
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This article contains material first reported in Wound Repair and Regeneration: Lindblad WJ, Kolb JE, Flood LC, et al. A late defect in wound healing associated with recurrent spontaneous pneumothoraces: a presumptive role for abnormal collagenase activity. Wound Repair and Regeneration 1995;3:15-24.
Address reprint requests to Dr McKneally, University of Toronto, Eaton North 10-230, 200 Elizabeth St, Toronto, Ont, Canada M5G 2C4.
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References
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- Lawrence WT. Clinical management of non-healing wounds. In: Cohen IK, Diegelmann RF, Lindblad WJ, eds. Wound healing: biochemical and clinical aspects. Philadelphia: Saunders, 1992:541-61.
- Beighton P, Horan FT. Surgical aspects of the Ehlers-Danlos Syndrome: a survey of 100 cases. Br J Surg 1969;56:255–9.[Medline]
- Eisen AZ, Bauer EA, Jeffrey JJ. Animal and human collagenases. J Invest Dermatol 1970;55:359–73.[Medline]
- Lovejoy B, Cleasby A, Hassell AM, et al. Structure of the catalytic domain of fibroblasst collagenase complexed with an inhibitor. Science 1994;263:375–7.[Abstract/Free Full Text]
- Eisenberg M, Stevens LH, Schofield PJ. Epidermolysis bullosa-new therapeutic approaches. Aust J Dermatol 1978;19:1–8.
- Bauer EA, Cooper TW, Tucker DR, Esterly NB. Phenytoin therapy of recessive dystrophic epidermolysis bullosa: clinical trial and proposed mechanism of action on collagenase. N Engl J Med 1980;303:776–81.[Abstract]
- Lindblad WJ, Kolb JE, Flood LC, et al. A late defect in wound healing associated with recurrent spontaneous pneumothoraces: a presumptive role for abnormal collagenase activity. Wound Rep Reg 1995;3:15–24.
- Roberts HR, Hoffman M. Hemophilia and related conditions-inherited deficiencies of prothrombin (factor II), factor V, and factors VII to XII. In: Beutler E, Lichtman M, Coller B, Kipps T, eds. Williams' hematology, 5th ed. New York: McGraw Hill, 1995:1413-39.
- Shapiro M. Acceleration of gingival wound healing in non-epileptic patients receiving diphenylhydantoin. Exp Med Surg 1958;16:41–53.
- Simpson GM, Kunz E, Slafta J. Use of sodium diphenylhydantoin in treatment of leg ulcers. NY State J Med 1965;65:886–8.[Medline]
- Smith B, Moore M, Jain K. Topical phenytoin and wound healing: report of the First International Conference on the Uses of Phenytoin in Dermatology. Int J Dermatol 1988;27:528–30.
- Lodha SC, Lohiya ML, Vyas MCR, Bhandari S, Goyal RR, Harsh MK. Role of phenytoin in healing of large abscess cavities. Br J Surg 1991;78:105–8.[Medline]
- Shafer WH, Beatty RE, Davis WB. Effect of dilantin sodium on tensile strength of healing wounds. Proc Soc Exp Biol Med 1958;98:349–50.
- Hassell TM. Evidence for production of an inactive collagenase by fibroblasts from phenytoin-enlarged human gingivae. J Oral Pathol 1982;11:310–7.[Medline]
- Chiu RC-J, Mulder DS. From the bedside to the laboratory and back. In: Troidl H, Spitzer WO, McKneally MF, et al, eds. Principles and practice of research: strategies for surgical investigators. 2nd ed. New York: Springer-Verlag, 1991:322-5.
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Abstract
Introduction
