Pure red cell aplasia (PRCA) is a rare bone marrow failure characterized by a progressive normocytic anemia and reticulocytopenia without leukopenia and thrombocytopenia. It can be associated with various hematological disorders but exceedingly rarely with angioimmunoblastic T-cell lymphoma (AITL). We report the case of a 72-year-old woman with PRCA associated with AITL. The patient presented with severe anemia (hemoglobin 2.6 g/dL) and a low reticulocyte count 0.7%. Direct and indirect Coombs tests were positive. A CT scan of the chest, abdomen, and pelvis revealed multiple lymphadenopathies. A cervical lymph node biopsy was compatible with AITL. A bone marrow biopsy showed medullary involvement by AITL and a severe erythroid hypoplasia with a myeloid:erythroid ratio of 19.70. The patient was started on CHOP and after 6 cycles the PET scan confirmed complete remission.virus in osteomedullary biopsy excluded the involvement of parvovirus B19. It can be presumed that positive parvovirus B19 and CMV serologies are related to cross-reactivity caused by hypergammaglobulinemia.The mechanisms behind the association with PRCA and lymphoproliferative diseases are not known. It is believed that there is a heterogenous ground that associates humoral factors from the tumor with the inhibitory action in the development of the erythroid lineage. PCRA may precede, occur simultaneously or after the diagnosis of a lymphoproliferative disease [4].Besides aggressiveness and poor prognosis of AITL associated with PRCA, this patient achieved a complete remission after the treatment and remains asymptomatic and without signs of active disease 1 year after the diagnosis.Nevertheless, the risk of relapse is high and the long-term prognosis is poor, requiring a close follow-up.

Background:The use of bone scintigraphy (Sc) in spondyloarthritis (SpA) as a technique for diagnosis, assessment of activity and treatment decision has been questioned by the scientific community. Due to its low cost compared to Magnetic Resonance Imaging - MRI (the gold standard)1, some studies proposed to evaluate Sc’s diagnostic accuracy. These studies have shown that Sc has a low diagnostic sensitivity of 50-55%2. Also, there is a poor correlation between symptoms and scintigraphic uptake3. We aimed to evaluate the use of Sc for management and follow-up of patients with SpA.Objectives:To determine if Sc activity correlates with patients’ complaints (peripheral and axial), inflammatory markers, disease activity scores and whether it influenced physicians’ treatment decisions during the follow-up of the disease.Methods:We performed a retrospective review of all patients at our department with SpA with at least one Sc from 2018 to 2020. The following variables were analyzed: demographic data, spondyloarthropathy subtype (ankylosing, enteropathic, psoriatic and undifferentiated SpA), axial or peripheral pain, Sc findings (inflammatory vs no-inflammatory activity), inflammatory markers (sedimentation rate - ESR and C-Reactive Protein - CRP), disease activity scores within one year since the Sc (Ankylosing Spondylitis Disease Activity Score with Erythrocyte Sedimentation Rate - ASDAS-ESR and Bath Ankylosing Spondylitis Disease Activity Index - BASDAI) and treatment at the time of the Sc (non-steroidal anti-inflammatory drugs, conventional synthetic disease-modifying antirheumatic drugs (DMARDs), target synthetic DMARDs and biologic DMARD. Treatment decisions (escalation, de-escalation or maintenance) in accordance to Sc results were also reviewed.We used the non-parametric Mann-Whitney’s U test for comparisons between ordinal or numerical variables. For correlations between categorical variables we used the Fisher’s exact test and the χ2-independence test. Tests with p < 0.05 were statistically significant.Results:Fifty-five patients were reviewed, 75% women; median age of 48 years. Seventy-one percent had ankylosing SpA, 15% enteropathic SpA, 5% psoriatic SpA, 5% undifferentiated and 4% reactive SpA. Sixty-two percent of the patients had both axial and peripheral pain and 24% only axial complaints. Sixty-two percent of the patients had a Sc with no inflammatory changes, 27% had peripheral and 25% had axial inflammatory changes; 15% had evidence of both peripheral and axial inflammation. For ankylosing SpA, the median ASDAS-ESR was 2.89 and according to the BASDAI, 66% had active disease. The median CRP and ESR in patients with inflammatory vs a normal Sc was not different (p=0.02 vs p=0.36, respectively). Similarly, Sc findings were not correlated with patients’ axial (p=0.10) or peripheral pain (p=1.0), neither with the ASDAS-ESR (p=0.29) or the BASDAI (p=0.29). There was no correlation between inflammatory activity in Sc and the decision to maintain, escalate or de-escalate treatment (p=0.65), including the decision to start a biological DMARD (p=1.0) or to switch between biological DMARDs (p=0.19).Conclusion:There was no correlation between Sc findings and ESR, patients’ complaints, disease activity or treatment decisions. Considering previous research showing a low diagnostic sensitivity, our findings seem to support a limited role of bone Sc for the follow-up and management of patients with seronegative SpA.References:[1]Khmelinskii N, Regel A, Baraliakos X. The Role of Imaging in Diagnosing Axial Spondyloarthritis. Front Med. 2018;5. doi:10.3389/fmed.2018.00106[2]Poddubnyy D. Classification vs diagnostic criteria: the challenge of diagnosing axial spondyloarthritis. Rheumatology. 2020;59(Supplement_4):iv6-iv17. doi:10.1093/rheumatology/keaa250[3]Shim JS, Kim C, Ryu JJ, Choi SJ. Correlation between TM joint disease and rheumatic diseases detected on bone scintigraphy and clinical factors. Sci Rep. 2020;10(1):4547. doi:10.1038/s41598-020-60804-xDisclosure of Interests:None declared.