A Case of Cytomegalovirus-Induced Hemophagocytic Lymphohistiocytosis in a Patient with an Underlying Rheumatic Disease

Clinical Presentations, Diagnosis, and Genetic Features of Hemophagocytic Lymphohistiocytosis: A Single Institutional Experience With the Saudi Population

Background Hemophagocytic lymphohistiocytosis (HLH) is an uncommon, potentially fatal condition caused by high immune activation. The present study aimed to identify the clinical manifestations, geographic distribution, and associated pathogenic genetic mutations of HLH in Saudi Arabia. Method A retrospective cross-sectional study was conducted at King Fahad Medical City (KFMC), with a total of 59 patients diagnosed with HLH in the period between 2006 and 2018. All genetic results and clinical and biochemical data were retrieved and statistically analyzed using IBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York, United States). Results The results revealed that 48 patients (81.4%) had 15 pathogenic mutations of primary HLH whereas 8 (13.6%) patients had no genetic mutation. The most common variant mutation identified was c.1430C>T of the STXBP2 gene (42.4% of total patients), followed by c.1122G>A of the PRF1 gene (10.2% of patients), which demonstrated a distinctive geographic and tribal association. Patients with RAB27A mutation tend to present at an older age than the others with a median age of presentation of 5.5 months vs 2 months for patients with PRF1 mutations. No significant differences in clinical features were observed among the various groups. Conclusion This study highlights the incidence of genetic mutations among the Saudi population with HLH. The STXBP2 is the most common mutation followed by PRF1 mutations, many mutation variants are associated with a distinctive tribal and geographic association.

Secondary haemophagocytic lymphohistiocytosis in a patient with new-onset systemic lupus erythematosus: the challenges of timely diagnosis and successful treatment

Haemophagocytic lymphohistiocytosis (HLH) is an immune-mediated disease driven by abnormal macrophage activation and regulatory cell dysfunction. HLH can be primary due to genetic mutations or secondary due to infection, malignancy or autoimmune conditions. We describe a woman in her early 30s who developed HLH while being treated for newly diagnosed systemic lupus erythematosus (SLE) complicated by lupus nephritis as well as concomitant cytomegalovirus (CMV) reactivation from a dormant infection. The trigger for this secondary form of HLH may have been either aggressive SLE and/or CMV reactivation. Despite prompt treatment with immunosuppressive therapies for SLE consisting of high-dose corticosteroids, mycophenolate mofetil, tacrolimus, etoposide for HLH and ganciclovir for CMV infection, the patient developed multiorgan failure and passed away. We demonstrate the difficulty in identifying a specific cause for secondary HLH when multiple conditions are present (SLE and CMV) and the fact that, despite aggressive treatment for both conditions, the mortality for HLH remains high.

Clinical characteristics and treatment of elderly onset adult-onset Still's disease

Adult-onset Still’s disease (AOSD)—a systemic inflammatory disease—often occurs at a young age. Recently, elderly onset patient proportion has been increasing; however, data are limited. To evaluate the characteristics of elderly patients with AOSD in a multicenter cohort, we retrospectively analyzed 62 patients with AOSD at five hospitals during April 2008–December 2020. Patients were divided into two groups according to age at disease onset: younger-onset (≤ 64 years) and elderly onset (≥ 65 years). Clinical symptoms, complications, laboratory findings, treatment, and outcomes were compared. Twenty-six (41.9%) patients developed AOSD at age ≥ 65 years. The elderly onset group had a lower frequency of sore throat (53.8% vs. 86.1%), higher frequency of pleuritis (46.2% vs. 16.7%), and higher complication rates of disseminated intravascular coagulation (30.8% vs. 8.3%) and macrophage activation syndrome (19.2% vs. 2.8%) than the younger onset group. Cytomegalovirus infections were frequent in elderly onset patients (38.5% vs. 13.9%) but decreased with early glucocorticoid dose reduction and increased immunosuppressant and tocilizumab use. Elderly AOSD is not uncommon; these patients have different characteristics than younger-onset patients. Devising a way to control disease activity quickly while managing infections may be an important goal in elderly AOSD.

Concomitant Hemophagocytic Lymphohistiocytosis and Cytomegalovirus Disease: A Case Based Systemic Review

Background

Hemophagocytic lymphohistiocytosis (HLH) is an immune mediated life-threatening condition. It is driven by an overactivation of the immune system and causes inflammatory tissue damage potentially leading to organ failure and death. Primary HLH is caused by genetic mutations, while secondary HLH is triggered by external factors. Viral infections are a well-known cause of secondary HLH. Cytomegalovirus (CMV) is a virus in the herpes family known to cause HLH in rare cases.

Methods

We report a recent case of CMV-induced HLH, followed by a systematic review of described cases of this rare disease entity, through a structured search in the medical database PubMed. All articles were assessed on a predetermined set of inclusion criteria.

Results

A total of 74 patients (age > 18 years) with CMV-related HLH were identified, 29 men, 42 women, and three patients with unspecified gender. Median age was 37.5 years (range 18-80). Sixty-six patients (88%) had one or more comorbid conditions and 22 patients (30%) had inflammatory bowel disease (IBD), the most frequent comorbidity. Forty patients (54%) received some form of immunomodulating treatment prior to HLH development. The general treatment approach was in general dual, consisting of antiviral treatment and specific immunomodulating HLH treatment approaches. Treatment outcome was at 77% survival, while 23% had fatal outcome.

Conclusion

The findings highlight the importance of early diagnostic work up and treatment intervention. Ability to recognize the characteristic clinical traits and perform specific HLH diagnostic workup are key factors to ensure targeted diagnostic work and treatment intervention for this patient group.