CLIPPERS features before, during and after lymphoma

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): contemporary advances and current controversies

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory syndrome with characteristic clinical, radiological, and pathological features, and can be effectively treated with corticosteroid-based immunotherapies. The exact pathogenesis of CLIPPERS remains unclear, and specific diagnostic biomarkers are not available. According to the 2017 diagnostic criteria, probable CLIPPERS should be considered in middle-aged patients with subacute onset of pontocerebellar symptoms and typical punctuate and curvilinear gadolinium enhancement lesions ("salt-and-pepper" appearance) located in the hindbrain (especially pons) on magnetic resonance imaging. In addition, CLIPPERS-mimics, such as central nervous system (CNS) lymphoma, and several antibody-associated autoimmune CNS diseases (e.g., myelin oligodendrocyte glycoprotein antibody-associated disease, autoimmune glial fibrillary acidic protein astrocytopathy, and anti-N-methyl-D-aspartate receptor encephalitis), should be extensively excluded. The prerequisite for definite CLIPPERS is the perivascular T-cell-predominant inflammatory infiltration observed on pathological analysis. A biopsy is strongly suggested when clinical/radiological red flags are present. Most patients with CLIPPERS respond well to corticosteroids and have a good prognosis. Long-term low-dose corticosteroid maintenance therapy or corticosteroids coupled with immunosuppressants are recommended to prevent the recurrence of the syndrome. The potential progression of CLIPPERS to lymphoma has been suggested in some cases; therefore, at least 2-year clinical and radiological follow-up is essential. Here, we critically review the recent developments and provided an update on the clinical characteristics, diagnostic criteria, differential diagnoses, and therapeutic management of CLIPPERS. We also discuss the current controversies in this context that can be resolved in future research studies.

Brain biopsy in patients with CLIPPERS syndrome: why and when

CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) is an inflammatory disorder of the central nervous system (CNS), predominantly involving the brainstem with a characteristic magnetic resonance imaging (MRI) appearance and clinical and radiological responsiveness to glucocorticosteroids. Yet diagnostic biomarkers are missing and other immune-mediated, (para-) infectious and malignant causes mimic CLIPPERS-like MRI presentations. We report the case of a 51-year-old male patient with CLIPPERS who repeatedly responded well to high-dose corticosteroids. After 7 months, however, treatment failed, and he had a biopsy-confirmed diagnosis of a CNS B-cell lymphoma. Clinical and MRI signs of CLIPPERS include a wide spectrum of differential diagnoses which often arise only later during the course of disease. Similar to the case presented here, delayed diagnosis and specific therapy may contribute to an unfavorable outcome. Hence, we propose that in the absence of other diagnostic markers, brain biopsy should be performed as early as possible in CLIPPERS patients.

CLIPPERS and its mimics: evaluation of new criteria for the diagnosis of CLIPPERS

OBJECTIVE

To evaluate the accuracy of the recently proposed diagnostic criteria for chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS).

METHODS

We enrolled 42 patients with hindbrain punctate and/or linear enhancements (<3 mm in diameter) and tested the CLIPPERS criteria.

RESULTS

After a median follow-up of 50 months (IQR 25-82), 13 out of 42 patients were CLIPPERS-mimics: systemic and central nervous system lymphomas (n=7), primary central nervous system angiitis (n=4) and autoimmune gliopathies (n=2). The sensitivity and specificity of the CLIPPERS criteria were 93% and 69%, respectively. Nodular enhancement ( ≥ 3 mm in diameter), considered as a red flag in CLIPPERS criteria, was present in 4 out of 13 CLIPPERS-mimics but also in 2 out of 29 patients with CLIPPERS, explaining the lack of sensitivity. Four out of 13 CLIPPERS-mimics who initially met the CLIPPERS criteria displayed red flags at the second attack with a median time of 5.5 months (min 3, max 18), explaining the lack of specificity. One of these four patients had antimyelin oligodendrocyte glycoprotein antibodies, and the three remaining patients relapsed despite a daily dose of prednisone/prednisolone ≥ 30 mg and a biopsy targeting atypical enhancing lesions revealed a lymphoma.

CONCLUSIONS

Our study highlights that (1) nodular enhancement should be considered more as an unusual finding than a red flag excluding the diagnosis of CLIPPERS; (2) red flags may occur up to 18 months after disease onset; (3) as opposed to CLIPPERS-mimics, no relapse occurs when the daily dose of prednisone/prednisolone is ≥ 30 mg; and (4) brain biopsy should target an atypical enhancing lesion when non-invasive investigations remain inconclusive.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma: Comparison of clinical features and risk factors suggestive of underlying lymphomas

BACKGROUND

We studied patients with chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma and measured risk factors suggestive of an underlying lymphoma and follow-up outcomes.

METHODS

CLIPPERS patients associated with or without lymphoma were included into this study. Clinical presentations were documented, risk factors suggestive of an underlying lymphoma were tested, and prognostic differences in terms of death were compared.

RESULTS

Ten patients had a diagnosis of CLIPPERS associated with lymphoma, with 6 B-cell non-Hodgkin lymphoma, 2 T-cell non-Hodgkin lymphoma and 2 Hodgkin lymphoma. Using multivariate logistic analysis, the following 3 independent risk factors were found to be related to a final diagnosis of lymphoma: hyperreflexia (HR 16.56; 95% CI 1.03-265.29; p = 0.032), elevated protein in CSF (HR 11.59; 95% CI 1.24-108.39; p = 0.047), and recurrences between 2 months and 1 year after treatment (HR 29.27; 95% CI 2.09-409.58; p = 0.012). The model calibration was satisfactory (p = 0.392 with the Hosmer-Lemeshow test), and the discrimination power was good (area under the receiver operating characteristic curve 0.921; p < 0.001, 95% CI 0.826-1.000). Patients with CLIPPERS associated with lymphoma had higher mortality rate and lymphoma was a significant predictor of total mortality (HR 0.040; 95% CI 0.006-0.262; p = 0.001).

CONCLUSIONS

Hyperreflexia, elevated protein in CSF and recurrences between 2 months and 1 year after treatment are risk factors suggesting an underlying lymphoma. Relapses during high-dose steroids maintenance therapy can be indicative of lymphoma, too. Patients having CLIPPERS associated with lymphoma have a worse prognosis than those without lymphoma.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) in limited cutaneous sclerosis: a rare disease combination

A 26-year-old patient of limited cutaneous sclerosis presented to us with insidious-onset posterior fossa symptoms of headache, vomiting, vertigo and gait imbalance, progressing over a period of 3 weeks. A diagnosis of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids was made by combining the clinical features with radiological evidence showing punctate infiltration of the pons, brainstem and cerebellum. Relevant differentials in the form of neurosarcoid, infections, central nervous system (CNS) lymphoma and Neuro-Behcet's disease were ruled out by history and investigations. The patient responded dramatically to steroid therapy, and had no neurological deficits after 18 months of follow-up. This case highlights the rare association of a not-so-common immunological disease with a rare neurological disease.