Splenectomy associated with increased risk of herpes zoster in a population-based cohort study

Risk factors for herpes zoster infections: a systematic review and meta-analysis unveiling common trends and heterogeneity patterns

PURPOSE

The burden of herpes zoster (HZ) is substantial and numerous chronic underlying conditions are known as predisposing risk factors for HZ onset. Thus, a comprehensive study is needed to synthesize existing evidence. This study aims to comprehensively identify these risk factors.

METHODS

A systematic literature search was done using MEDLINE via PubMed, EMBASE and Web of Science for studies published from January 1, 2003 to January 1, 2023. A random-effects model was used to estimate pooled Odds Ratios (OR). Heterogeneity was assessed using the I2 statistic. For sensitivity analyses basic outlier removal, leave-one-out validation and Graphic Display of Heterogeneity (GOSH) plots with different algorithms were employed to further analyze heterogeneity patterns. Finally, a multiple meta-regression was conducted.

RESULTS

Of 6392 considered records, 80 were included in the meta-analysis. 21 different conditions were identified as potential risk factors for HZ: asthma, autoimmune disorders, cancer, cardiovascular disorders, chronic heart failure (CHF), chronic obstructive pulmonary disorder (COPD), depression, diabetes, digestive disorders, endocrine and metabolic disorders, hematological disorders, HIV, inflammatory bowel disease (IBD), mental health conditions, musculoskeletal disorders, neurological disorders, psoriasis, renal disorders, rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and transplantation. Transplantation was associated with the highest risk of HZ (OR = 4.51 (95% CI [1.9-10.7])). Other risk factors ranged from OR = 1.17-2.87, indicating an increased risk for all underlying conditions. Heterogeneity was substantial in all provided analyses. Sensitivity analyses showed comparable results regarding the pooled effects and heterogeneity.

CONCLUSIONS

This study showed an increased risk of HZ infections for all identified factors.

HSV Encephalomyelitis in an Immunocompetent Patient With Prior Splenectomy

A 44-year-old male with history of asplenia, provoked PE, and hyperlipidemia presented with ascending paralysis, bowel and bladder incontinence and altered mental status, and progressively developed acute hypoxic respiratory failure. Initial workup including CT head, magnetic resonance imaging (MRI) brain, and lumbar puncture which was concerning for herpes simplex virus (HSV) meningoencephalitis; out of caution he was started on multiple antibiotics consequently resulting in the development of Clostridium difficile (C.diff). He also received two doses of IVIG. He was transferred to our institution and after interval re-imaging via MRI brain and spinal surveys and repeat lumbar punctures, he was found to have a high CSF HSV titer and positive GAD 65 antibody, the latter likely a false positive due to IVIG administration. IVIG was not continued from the outside hospital due to the development of deep vein thrombosis (DVT), and the risks of plasmapheresis outweighed the benefits. The patient gradually improved after a prolonged course of acyclovir and was downgraded out of the Neuroscience ICU (NSICU), however decompensated due to rectal bleeding, and subsequently went into cardiac arrest. Though this patient underwent a splenectomy, his relative immunocompetency towards non-encapsulated organisms should have been preserved. It has not been clearly described in the literature how and why HSV encephalomyelitis takes a fulminant course in immunocompetent patients, including our asplenic patient. Furthermore, definitive treatment and management of this condition remains unclear. Severity of HSV encephalomyelitis has not been clearly described in the literature, particularly in immunocompetent patients (such as this asplenic patient).

Risk of herpes zoster infection in men with varicocele

PURPOSE

Several diseases have been identified as stressful factors for herpes zoster (HZ) infection. In this study, we investigated the risk of HZ infection in men with varicocele.

METHODS

We enlisted the data of patients with newly diagnosed varicocele between 2000 and 2012 from the Taiwanese National Health Insurance Research Database as case cohort. Four control patients were matched as per age and index year to a case patient. HZ diagnosis was the primary end point, and the follow-up period was considered as the time interval from the index date to the main outcome, withdrawal from the National Health Insurance program, or end of the study (31 December 2013).

RESULTS

In total, 8720 patients were recruited (1744 with varicocele and 6976 controls); the overall mean age was 36 years. Majority (85%) of the participants were 20-49 years old. HZ incidence was higher in patients with varicocele (5.60 per 1,000 person-years) than in the control group (4.01 per 1,000 person years). Patients with varicocele were 1.37 times more likely to develop HZ than the controls after adjustment. Compared with the control cohort, the adjusted hazards ratio (HR) of the varicocele cohort was higher in patients younger than 49 years old (adjusted HR = 1.60).

CONCLUSION

Men with varicocele had a higher risk of HZ development than those without varicocele, particularly those aged ≤49 years. Thus, stress from varicocele cannot be ignored in young men.