Pyoderma gangrenosum in myelodysplasia and acute leukaemia

Bullous Variant of Pyoderma Gangrenosum in a Patient with Acute Myeloid Leukemia

Unlike classic pyoderma gangrenosum (PG), the bullous variant of PG is typically represented by a painful erythematous papule, plaque, and superficial bulla that progress into the ulceration with bullous margin. Generally, bullous PG is most commonly associated with myeloproliferative disorders, such as acute myeloid leukemia (AML). Bullous PG in AML patients rarely occurs, but once it does, it suggests a poor clinical prognosis. Although many cases of classic PG in AML patients have been reported, bullous PG is relatively rare. Therefore, we present a case of bullous PG that developed in a patient with AML and was successfully treated with high-dose systemic steroids.

Pyoderma gangrenosum in hematologic malignancies: A systematic review

BACKGROUND

Pyoderma gangrenosum (PG) is a devastating neutrophilic dermatosis that may be associated with trauma or systemic diseases. The associations, characteristics, and temporal relationship of PG with hematologic malignancies are not well understood.

OBJECTIVE

We performed a systematic review of PG associated with hematologic malignancies using data from case reports, case series, and retrospective studies.

METHODS

We searched MEDLINE, EMBASE, Scopus, and Web of Science from each database's inception to December 12, 2018. Two reviewers independently selected studies and extracted data.

RESULTS

Two hundred seventy-nine publications met the inclusion criteria (340 cases). Myelodysplastic syndrome (MDS) was the most commonly reported hematologic malignancy associated with PG, followed by monoclonal gammopathy of undetermined significance and acute myeloid leukemia. The mean age of patients was 56.5 years, with males being more common. There was a predominance of the ulcerative PG subtype and multifocal distributions across all hematologic malignancies. The majority of MDS cases preceded PG, which was reversed for MGUS.

LIMITATIONS

The data were limited by reporting bias because PG subtypes rely on the rendered diagnosis reported. In addition, the classification for hematologic malignancies has evolved since 1978.

CONCLUSION

Patients with PG should be evaluated for hematologic malignancies, with MDS being the most common.

Azacitidine-induced pyoderma gangrenosum at injection sites in a patient with myelodysplastic syndrome

Pyoderma gangrenosum (pg) is a rare neutrophilic dermatosis characterized by painful necrotic ulceration affecting preferentially the lower extremities. Diagnosis is challenging, and a thorough workup (including biopsy) is required. In this case report, we describe a 67-year-old patient with a diagnosis of myelodysplastic syndrome (mds) who developed fever and pg two days after the first cycle of subcutaneous azacitidine (Vidaza; Celgene Corporation, Summit, NJ, USA). On physical examination, the patient had four erythematous plaques at sites of subcutaneous injections of azacitidine on the arms, as well as three other plaques in proximity. A skin biopsy demonstrated a dense neutrophilic interstitial infiltrate in the dermis. After the diagnosis of pg, prednisone 1 mg/kg was started and the fever subsided rapidly. This was followed by the resolution of the cutaneous lesions. Changing the route of administration of azacitidine from subcutaneous to intravenous and adding a daily dose of prednisone during the treatment allowed the patient to receive a total of 10 cycles of azacitidine. This is the second case reported in the literature. Because azacitidine is frequently used in mds and acute myeloid leukemia, clinicians should be aware of this rare cutaneous adverse event. Our approach can be used to avoid the recurrence of pg when continuing azacitidine treatment.

Trizentrische Analyse von Kofaktoren und Komorbidität des Pyoderma gangraenosum

EINLEITUNG

Das Pyoderma gangraenosum (PG) ist eine seltene, inflammatorische destruktiv-ulzerierende neutrophile Erkrankung mit weitgehend unklarer Pathophysiologie.

MATERIAL UND METHODIK

In dieser Studie wurden die potenziell relevanten Kofaktoren und Begleiterkrankungen von Patienten mit PG aus drei dermatologischen Wundzentren in Deutschland differenziert ausgewertet.

ERGEBNISSE

Von den insgesamt 121 analysierten Patienten waren Frauen (66,9 %) häufiger betroffen als Männer. Das Alter der Patienten war 18-96 Jahre (Mittelwert [MW]: 59,8); die Wunden hatten eine Größe von 1-600 cm² (MW: 65,6 cm²) und waren überwiegend sehr schmerzhaft (VAS 1-10, MW: 7). Die Unterschenkel waren am häufigsten (71,9 %) betroffen. Bei 12 (9,9 %) Patienten bestanden chronisch entzündliche Darmerkrankungen (5,8 % Colitis ulcerosa; 4,1 % Morbus Crohn), bei 14,1 % der Patienten wurde eine Begleiterkrankung aus dem rheumatischen Formenkreis beschrieben. Neoplasien bestanden bei 20,6 % der Patienten, von denen 6,6 % als hämatologische und 14,1 % als solide Neoplasien klassifiziert wurden. Aus dem Kreis des metabolischen Syndroms wurde bei 69,4 % Patienten eine Adipositas, bei 57,9 % eine arterielle Hypertonie und bei 33,9 % ein Diabetes mellitus diagnostiziert.

SCHLUSSFOLGERUNGEN

Diese Datenanalyse bestätigt Assoziationen des PG mit dem metabolischen Syndrom und mit Neoplasien, die zukünftig frühzeitig bei einer zielgerichteten Diagnostik der Patienten beachtet und behandelt werden sollten.

Tricenter analysis of cofactors and comorbidity in patients with pyoderma gangrenosum

INTRODUCTION

Pyoderma gangrenosum (PG) is a rare neutrophilic, ulcerative skin disease of largely unknown pathophysiology.

MATERIAL AND METHODS

In this study, potentially relevant cofactors and comorbidities in patients with PG from three dermatological wound care centers in Germany were evaluated.

RESULTS

Of the 121 patients assessed, women (66.9 %) were more frequently affected than men. Patient age ranged from 18 to 96 years (mean 59.8). Wound size varied from 1-600 cm² (mean 65.6 cm²), and the pain intensity was predominantly very high (VAS 1-10, mean 7). The lower legs were most commonly (71.9 %) affected. Overall, 12 (9.9 %) patients had inflammatory bowel disease (ulcerative colitis, 5.8 %; Crohn's disease, 4.1 %), 14.1 % exhibited rheumatic comorbidities. Neoplasms were found in 20.6 % of patients, with 6.6 % classified as hematological and 14.0 % as solid neoplasms. With respect to criteria for the metabolic syndrome, obesity was found in 69.4 %, arterial hypertension in 57.9 %, and diabetes mellitus in 33.9 % of patients.

CONCLUSIONS

The present data analysis confirms the association of PG with metabolic syndrome and neoplasms. In the future, these aspects should be included in the targeted diagnostic workup of patients with PG and subsequently treated in a timely fashion.

Pyoderma Gangrenosum

Pyoderma Gangrenosum is cutaneous manifestation of a systemic problem that should be systematically diagnosed and managed with care. When such lesions appear on legs, it is important to study and treat the systematic problem.

Bullous pyoderma gangrenosum associated with pancytopenia of unknown origin

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis of unknown origin. Clinically it starts with a pustule, nodule or bulla that rapidly progresses and turns into a painful ulcer with raised, undermined borders. The etiopathogenesis of PG remains unknown. However it is frequently associated with systemic diseases such as inflammatory bowel disease (IBD), haematological disorders or arthritis. The latest multicentric retrospective analysis published by Ghazal et al. shows that anaemia has been observed very often in German patients suffering from PG (in 45.6% of 259) so this disorder is supposed to be a possible cofactor in the pathogenesis of PG. According to its progressive course, patients require intensive diagnostic procedures and rapid initiation of the treatment. In this article, we report a case of bullous pyoderma gangrenosum in association with pancytopenia of unknown origin, according to its diagnostic and therapeutic difficulties.

Pyoderma gangrenosum successfully treated with antiretroviral therapy alone in a human immunodeficiency virus-infected individual

We report a case of a 60-year-old man infected with human immunodeficiency virus (HIV) who was transferred to our hospital for management of multiple non-healing, painful ulcers on the lower extremities. The histological findings of the biopsy specimen were compatible with the diagnosis of pyoderma gangrenosum (PG). An association between HIV infection and the development of PG was considered after a thorough investigation. Antiretroviral therapy without the use of adjunctive immunosuppressive agents resulted in clinical improvement. Our case implies that antiretroviral therapy alone could heal PG in untreated HIV-infected patients.

Etiology and management of pyoderma gangrenosum: a comprehensive review

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis characterized by painful, necrotic ulceration. It typically affects patients in the third to sixth decades of life, with almost equal incidence in men and women. PG occurs most frequently on the lower extremities. Five clinical variants are currently recognized: classic, bullous, pustular, vegetative, and peristomal types. Half of PG cases are seen in association with systemic disease. Mimickers include infection, vascular insufficiency ulcers, systemic vasculitides, autoimmune disease, cancer, and exogenous tissue injury, among others. PG is often a diagnosis of exclusion, as there are no specific laboratory or histopathologic findings to confirm the diagnosis. PG thus presents many clinical challenges: it is difficult to diagnose, is frequently misdiagnosed, and often requires a work-up for underlying systemic disease. Successful management of PG typically requires multiple modalities to reduce inflammation and optimize wound healing, in addition to treatment of any underlying diseases. Prednisone and cyclosporine have been mainstays of systemic treatment for PG, although increasing evidence supports the use of biologic therapies, such as tumor necrosis factor-α inhibitors, for refractory cases of PG. Here, we review the clinical presentation and pathophysiology of PG, as well as its associated conditions, diagnostic work-up, and management.

Pyoderma gangrenosum: a rare cause of breast ulceration

Breast ulceration is an alarming sign for clinicians and places a significant physical and psychological burden on the patient. We report a rare presentation of pyoderma gangrenosum of the breast in a patient known to have ulcerative colitis but no active underlying disease process and no history of breast tissue trauma. This case report with literature review highlights the importance of considering pyoderma gangrenosum as a differential diagnosis in breast ulcers.

[Management of pyoderma gangrenosum. An update on clinical features, diagnosis and therapy]

Pyoderma gangrenosum is a rare neutrophilic inflammatory skin disease, mostly observed in middle-aged adults. Etiology and pathogenesis remain unclear. Autoimmune mechanisms including immune complex-mediated neutrophilic vascular reactions have been suggested. The hallmark finding in pyoderma gangrenosum is painful ulcers with sharply circumscribed and demarcated, frequently undermined, livid borders and a necrotic base. Pyoderma gangrenosum has been described in association with a great variety of systemic disorders, ranging from inflammatory bowel diseases to myeloproliferative disorders. The diagnosis of pyoderma gangrenosum is based primarily on the clinical presentation and course. It is usually a diagnosis of exclusion. Histopathological and laboratory findings in pyoderma gangrenosum are nonspecific. The aims of therapy are the complete suppression of inflammatory disease activity, promotion of wound healing and control of pain. Frequently, successful treatment of associated diseases leads to an improvement or complete remission of pyoderma gangrenosum. Surgical interventions, including aggressive ulcer excision, recipient site preparation and autologous skin grafting have to be avoided during the active phase of the disease because the likely occurrence of pathergy inducing new lesions at surgical sites and causing a worsening the original lesions.

Bullous pyoderma gangrenosum as the presenting sign of fatal acute myelogenous leukemia

Bullous pyoderma gangrenosum begins as a bulla, nodule or nonulcerated erythematous plaque that blisters or ulcerates to form a superficial ulcer surrounded by a hemorrhagic, bullous border, which is surrounded by a blue-gray halo. Bullous pyoderma gangrenosum is most commonly associated with hematologic malignancies, specifically, acute myelogenous leukemia (AML). We report a patient whose initial presentation with bullous pyoderma gangrenosum prompted the appropriate diagnostic evaluation and confirmation of AML, which was ultimately fatal. We emphasize that a thorough hematologic investigation, including bone marrow biopsy, should be performed in all patients who present with lesions clinically suggestive of bullous pyoderma gangrenosum because the skin lesion may be the only indicator of the underlying hematologic disorder.

Pyoderma gangrenosum: Clinical presentation and outcome in 18 cases and review of the literature

BACKGROUND

Pyoderma gangrenosum (PG) is an idiopathic ulcerative neutrophilic inflammatory skin disease characterized by variable clinical presentation and outcome. Because its incidence is low, no prospective randomized controlled trials and only a few large case studies on PG have been reported.

OBSERVATIONS

We demonstrate the clinical presentation and outcome in 18 cases with severe and chronic PG. In our 18 patients, the female/male ratio was 3.5:1, the mean onset age was 53.1 yrs (range 23-78); six cases (33%) had associated diseases (inflammatory bowel disease [n = 2, 11%], monoclonal gammopathy [n = 2, 11%], rheumatoid arthritis [n = 1, 6%], diabetes mellitus [n = 1, 6%]). Anatomic locations involved were lower leg (n = 14, 78%), abdomen (n = 5, 28%), arm (n = 3, 17%), breast (n = 2, 11%), and buttocks (n = 1,6%). Five patients (28%) had multiple lesions (n > or = 2). Immunosuppressive monotherapies (n = 3, 17%) and polytherapies (n = 15, 83%) were used. 13 patients (72%) showed complete remission (mean duration to complete remission: 1.29 yrs), three patients (17%) persistent disease (mean duration: 8 yrs), contact was lost to one patient (6%) and one patient died (6%).

CONCLUSION

Our observations add to the growing body of evidence that PG responds in most cases to systemic immunosuppressive treatment, with corticosteroids and cyclosporine representing first-line therapies. Besides reporting the clinical outcome in our 18 patients, we review the literature and discuss treatment recommendations that take additional factors including associated conditions, disease severity and localization of lesions into consideration.

Pyoderma gangrenosum: uncommon presentations

Pyoderma gangrenosum (PG) is a rare, inflammatory, noninfective, nonneoplastic skin disorder, which is often associated with systemic diseases. These include inflammatory bowel disease, rheumatoid arthritis, paraproteinaemia, or hematologic malignancy, which can be found in up to 50% of patients with some variants of PG. Brunsting et al (Arch Dermatol 1930;22:655-80) first described PG as a disease entity in 5 patients who had painful, enlarging necrotic ulcers with bluish undermined borders surrounded by advancing zones of erythema. Four of these patients had chronic ulcerative colitis. They felt that the condition might be associated with bacterial infection (pyoderma) and considered it as linked to the underlying bowel disease. Although the cause of PG remains obscure, bacterial infection seems to be unrelated to its causation, rendering the term pyoderma redundant. In addition, the number of conditions reported in association with PG has markedly expanded in recent years, showing clearly that this is not solely a cutaneous manifestation of inflammatory bowel disease. The clinical concept of PG has also been broadened, and certain clinical variants of PG have been linked with different types of associated disease seen in these patients.

Pyoderma gangrenosum: a review

Since its first description in 1930, the pathogenesis of pyoderma gangrenosum (PG) has remained obscure even as an ever-widening array of systemic diseases has been described in association with it. The histopathologic distinction of PG from other ulcerative processes with dermal neutrophilia is challenging and at times impossible. In consequence, when confronted with a biopsy from such a lesion, the pathologist has an obligation to obtain a full and detailed clinical history. In short, as a diagnosis of PG does not hinge exclusively upon the biopsy findings in isolation from other studies, a solid knowledge of the clinical features, the systemic disease associations and the differential diagnosis will help the pathologist to avoid diagnostic pitfalls or the generation of a report which is non-contributory to patient care. In this review, we describe in detail the different clinicopathologic forms of PG, summarize the diseases associated with this process in the literature and in our experience, and briefly review the treatment options.

[Skin manifestations associated with myelodysplastic syndromes]

PURPOSE

Our purpose was to describe cutaneous manifestations associated with myelodysplastic syndromes.

METHODS

Data from seven patients with cutaneous vasculitis (four cases), neutrophilic dermatosis (one case), relapsing polychondritis (one case), and possible erythema elevatum diutinum (one case) in association with myelodysplastic syndrome (refractory anaemia RA, RA with excess of blasts--RAEB-, RAEB in transformation RAEBt, chronic myelomonocytic leukaemia--CMML-), and analysis of the literature were reviewed.

RESULTS

The cutaneous manifestations of myelodysplastic syndrome may or may not be specific, and may reveal hemopathy transformation. The cutaneous vasculitis are the most frequent and polymorphic. The relation with neutrophilic dermatosis is more specific; they are a spectrum of diseases including pyoderma gangrenosum, Sweet's syndrome, erythema elevatum diutinum (nuclear segmentation anomalies of neutrophils both in the skin and in the blood are a biological marker of the association). Relapsing polychondritis is significantly associated with myelodysplastic syndromes. Their pathogenesis are controversial.

CONCLUSION

Early biopsy of cutaneous lesions in myelodysplastic syndromes is indicated. Analysis of blood cell count (and more bone marrow biopsy in relapsing polychondritis) is indispensable in these neutrophilic cutaneous or vasculitis diseases.

Myelodysplastic syndrome and associated skin lesions: a review of the literature

The skin involvement of the myelodysplastic syndrome (MDS) can take the form of either a neoplastic infiltration or various non specific lesions. The occurrence of these lesions may be the presenting feature of the disease (MDS) or may herald its progression to acute leukemia. Recognition and early diagnosis have therapeutic and prognostic significance.

Pyoderma gangrenosum: classification and management

Pyoderma gangrenosum (PG) has four distinctive clinical and histologic variants. Some have morphologic and histologic overlapping features with other reactive neutrophilic skin conditions. PG often occurs in association with a systemic disease, and the specific clinical features of the skin lesion may provide a clue to the associated disease. Management of PG depends on its type and severity and usually requires aggressive local and systemic treatment.

Myelodysplastic syndromes in the elderly: the role of growth factors in management

Myelodysplastic syndrome (MDS) comprises a group of heterogeneous clonal bone marrow disorders leading to peripheral cytopenia(s) and hypercellular marrow in the majority of the patients. The morphology of the cell lines is characterized by dysplastic features in some or all cell lines. The FAB classification has divided MDS in five subgroups, namely (1) RA (refractory anemia); (2) RARS (refractory anemia with ring sideroblasts); (3) CMML (chronic myelomonocytic leukemia); (4) RAEB (refractory anemia with excess blasts); and (5) RAEB-T (refractory anemia with excess blasts in transformation). Myelodysplastic syndrome remains primarily a disease of the elderly. With a reported median age of 74.4 years, patients have a chronic relentless course with complication of cytopenias, and a significant number of MDS patients, especially from the RAEB and RAEB-T categories, end up in acute myeloid leukemic transformation. Cytogenetic abnormalities are present in 40-58% of the cases and can provide not only help in diagnosis, but also understanding regarding the clinical course and prognostic aspect. Management of MDS is quite pragmatic and at this stage far from satisfactory. Various modalities have included use of differentiating agents, aggressive chemotherapy, bone marrow transplant and, more recently, significant interest has been generated in the use of hematopoietic growth factors. Differentiating agent trials have been unrewarding so far; chemotherapy trials have resulted in less benefit and more early toxic deaths, especially in the elderly MDS patients where the disease predominates. Bone marrow transplant appears suitable for some patients who are at a younger age. Salvation from this disease is being searched in the proper usage of hematopoietic growth factors and cytokines. There has been concern, however, that usage of growth factors has led to early and enhanced transformation of these patients to frank acute leukemic states. This concept appears to be somewhat refuted by newer controlled trials with GM-CSF and G-CSF, emphasizing that the acute leukemic transformation is the natural course of the disease and is not hastened by growth factor use. Preliminary studies are also suggesting that a combination of growth factors, especially G-CSF and erythropoietin as compared to chemotherapies, could be more beneficial in prolonging the survival of MDS patients who have progressed to the acute leukemic phase. More studies are needed for the understanding of the pathogenetic mechanism(s) in order to facilitate a more suitable and appropriate management strategy for MDS.

Unusual specific cutaneous lesions in myelodysplastic syndromes

BACKGROUND

Early diagnosis of leukemia cutis in myelodysplastic syndrome (MDS) is important because these lesions can precede acute peripheral blood or bone marrow transformation. Leukemia cutis is usually easy to recognize, but atypical lesions are not well described.

OBJECTIVE

Our purpose was to describe unusual specific lesions in MDS.

METHODS

Data from patients with myeloid malignancies and leukemia cutis were reviewed. Only patients with MDS and cutaneous lesions different from typical tumors were included. Clinical features were analyzed.

RESULTS

Four patients with MDS and unusual specific cutaneous lesions were found. They had ecchymoses, necrotic plaques or ulcers, and prurigo-like lesions. In three of four patients appearance of these skin lesions heralded or was concomitant with acute transformation.

CONCLUSION

Specific cutaneous lesions can display unusual patterns. Early biopsy of cutaneous lesions in MDS is indicated.

Simultaneous occurrence of two rare cutaneous markers of poor prognosis in myelodysplastic syndrome: erythema elevatum diutinum and specific lesions

We report the concomitant occurrence of erythema elevatum diutinum and specific skin lesions in a patient with a myelodysplastic syndrome (MDS). This patient's course, and review of other reported cases, support the opinion that neutrophilic dermatoses are associated with a poor prognosis of MDS. The simultaneous appearance of these manifestations could be the consequence of a particular chemotactism of myeloid cells, expressed after acute transformation.

Bullous pyoderma gangrenosum

Pyoderma gangrenosum is a necrotizing, ulcerative process commonly associated with inflammatory bowel disease but also occurring in several other systemic illnesses. When associated with myelodysplastic syndromes, its clinical appearance is often atypical. We describe a patient with severe, refractory bullous pyoderma gangrenosum. At autopsy cardiac involvement was demonstrated, a finding not previously reported. Patients with this unusual variant of pyoderma gangrenosum have a grave prognosis.

Paraneoplastic pyoderma gangrenosum

Pyoderma Gangrenosum (PG) is often associated with an underlying disease. PG as a paraneoplastic disease is illustrated by the presentation of four patients with malignancy of myeloproliferative origin and PG. An associated malignancy is found in approximately 7% of patients with PG, most commonly haematologic in nature and in particular leukaemia. Clinically the PG is often of the superficial bullous variant and is associated with a poor prognosis.

Myelodysplasia, vasculitis and anti-neutrophil cytoplasm antibodies

A cutaneous or systemic vasculitis occurs in myelodysplasia as well as in myeloproliferative and lymphoproliferative disorders. The most common lesion is a leucocytoclastic vasculitis, with neurological or joint involvement occurring less often. The vasculitis may appear contemporaneously with or precede the clinical onset of the blood dyscrasia. Occasionally the lesions respond dramatically to the use of steroids but in general, patients with vasculitis have a worse prognosis than those with uncomplicated myelodysplasia. Vasculitis and myelodysplasia appear together too often for the association to be coincidental and the vasculitis in most cases cannot be attributed to intercurrent infections, therapeutic agents or a pre-existing rheumatological disorder. While autoantibodies are frequently present in myelodysplasia, and ANA and anti-neutrophil cytoplasm antibodies (ANCA) are found in other vasculitides, neither of these antibodies is associated with the vasculitis of myelodysplasia. There has however been one report of ANCA in Sweet's syndrome a non-vasculitic skin condition that also occurs in the myelodysplastic syndromes.

Pyoderma gangrenosum, polycythemia rubra vera, and the development of leukemia

A patient with long-standing, well-controlled polycythemia rubra vera developed recurrent episodes of bullous pyoderma gangrenosum followed by the transformation of his hematologic disease into a rapidly progressive acute myeloid leukemia. This case, together with previously described patients, indicates that the appearance of bullous pyoderma gangrenosum in a patient with polycythemia rubra vera is often of ominous prognostic significance.

Fatal pyoderma gangrenosum in association with C7 deficiency

Although pyoderma gangrenosum (PG) is often associated with systemic diseases, it has not been reported in association with congenital complement deficiencies. We describe an aggressive and ultimately fatal case of PG in a patient with a congenital C7 deficiency. Deficiencies of C7 can be associated with decreased neutrophil chemotaxis, phagocytosis, and opsonization, similar to the immunologic abnormalities described in patients with PG. Our patient's decreased complement level, if not directly related to the development of PG, may have contributed to the aggressive nature of her disease.

Clinical features of MDS

MDS is primarily a disease of the elderly. Cases who give a history of exposure to X-rays, cytotoxic drugs or leukaemogenic chemicals may be younger. Many cases of MDS present because of an incidental blood count. The most prominent clinical features are those of anaemia, neutropenia, thrombocytopenia. Because haemopoietic tissue is also dysfunctional the pathological effect is often greater than the figures would suggest, even leading to infection of bleeding with normal neutrophil or platelet counts. Occult abscesses are a particular feature. Despite documented abnormalities of the lymphoid system, neither infections characteristic of T-cell immunodeficiency nor autoimmunity is a problem. The proliferation of monocytes in CMML leads to organomegaly, leukaemia cutis, serous effusions and vasculitic lesions caused by the mishandling of circulating immune complexes. Cancer is no commoner than in age-matched controls, but coincident lymphoid tumours do occur. Many patients require long-term blood transfusion and will run into problems of iron overload unless precautions are taken.

Pyoderma gangrenosum in childhood leukemia

A case of pyoderma gangrenosum (PG) in a 14-year-old boy with acute myelogenous leukemia (AML) is described. The onset of pyoderma gangrenosum coincided with the relapse of AML. The lesions responded dramatically to treatment with oral prednisone despite the persistence of leukemia. Pyoderma gangrenosum should be included in the differential diagnosis of any nodular, pustular, or necrotic cutaneous eruption in children with leukemia.

The myelodysplastic syndromes. Case report and review

The myelodysplastic syndromes are a heterogenous group of hematologic disorders of myeloid progenitor cells. Oral manifestations may be among the first signs and often reflect degrees of neutropenia or neutrophil dysfunction. A patient with persistent herpes labialis and severe oral mucosal ulceration in myelodysplastic syndrome is reported. The features of myelodysplasia are reviewed and their oral manifestations and significance to dental management outlined.

Pyoderma gangrenosum associated with erythroid hypoplasia

Pyoderma gangrenosum is most commonly associated with inflammatory bowel disease and rheumatoid arthritis, but it has been associated with various haematological malignancies. We describe its association with primary erythroid hypoplasia without thymoma in an 80 year old woman who presented with septicaemia complicating urinary tract infection. Spontaneous healing of an extensive lesion was observed.

Pyoderma gangrenosum and myelodysplasia

Pyoderma gangrenosum has been recognized occurring in association with acute and chronic leukaemia. More recently it has been described in patients with myelodysplasia (Jacobs, Palmer & Gordon-Smith 1985). We report a case of pyoderma gangrenosum in a patient with a preceding history of myelodysplasia, illustrating the problem of controlling the skin disease in this condition and the eventual transformation of the myelodysplasia into acute leukaemia. Treatment of the leukaemia resulted in improvement of the skin lesions.