Thiotepa is a common alkylating agent known to precipitate cutaneous reactions consistent with toxic erythema of chemotherapy, including erythema and hyperpigmentation. Herein, we describe an atypical case of malignant intertrigo involving preferential erythema and desquamation not only of skin folds but also of occluded areas after thiotepa-based conditioning. The diagnosis was complicated by concurrent stomatitis and oral petechiae in the setting of autologous stem cell transplant 11 days prior for diffuse large B-cell lymphoma. Histopathological examination from two cutaneous sites demonstrated epidermal dysmaturation and eccrine gland necrosis consistent with thiotepa-induced desquamation and not Stevens-Johnson syndrome or graft-versus-host-disease. Malignant intertrigo can present with extensive cutaneous involvement, as evidenced by our patient who had 25% body surface area affected. Mucosal involvement is common with most chemotherapeutic regimens and its presence should not deter the astute clinician from consideration of a diagnosis of toxic erythema of chemotherapy. No further interventions were needed and the patient healed spontaneously.

The original article was published on February 15, 2020 and corrected on March 15, 2020.The revised version of the article corrects the contact information of the Corresponding Author. The changes appear in the revised online PDF copy of this article.

Background

Joint replacements continue to occur during a rheumatoid arthritis (RA) patient's lifetime despite significant advances in available treatment options. The purpose of this study was to examine and quantify synovitis in surgically operated joints by ultrasound (US) in RA patients starting a new therapeutic agent.

Methods

RA subjects were enrolled in either tocilizumab or tofacitinib open-label, investigator-initiated trials and were assessed by ultrasound. In a subset of RA patients with joint replacements and/or operations of joint areas (OJA; e.g. joint arthroscopies, fusions, and synovectomies), joint-level scores of synovitis were compared between replaced joints, OJAs, and native joints. Joint-level synovitis was measured by grayscale (GSUS (0-3)) and power Doppler (PDUS (0-3)) at baseline and follow-up (3-6 months). McNemar's test or Wilcoxon signed rank test utilized the mixed effects ordinal logistic regression models.

Results

Twenty RA patients had a total of 25 replaced joints and 24 OJA. All replaced joints had GSUS> 1 and 92% had PDUS> 1 at baseline, while OJA and native joints had lower evidence of GSUS> 1 (37.5, 38% respectively) and PDUS> 1 (45.8, 62% respectively). GSUS and PDUS semiquantitative scores improved significantly with treatment in replaced joints (p = 0.01, p = 0.007), and native joints (p < 0.001 both), but not OJA.

Conclusions

In RA, joint replacement does not eliminate or prevent ultrasound measured synovitis, where all replaced joints have some evidence of US synovitis. US can also act as a potential marker of response to therapy in replaced joints. Scoring US synovitis in replaced joints should be considered in ultrasound RA clinical trials.

Trial registration

ClinicalTrials.gov NCT01717859 (registered 10/31/2012); ClinicalTrials.gov NCT02321930 (registered 12/22/2014).