Cytomorphologic Features Found in Cerebrospinal Fluid Specimens of Hemophagocytic Lymphohistiocytosis Patients.

OBJECTIVES: Central nervous system involvement is present in 70% of patients with hemophagocytic lymphohistiocytosis (CNS-HLH). CNS-HLH is defined by neurologic deficits, neuroimaging abnormalities, or positive cerebrospinal fluid (CSF) findings. The CSF cytomorphologic spectrum of CNS-HLH, however, has not been well investigated. METHODS: A retrospective review was performed on 64 CSF specimens from pediatric and adult patients with HLH. Ten patients had clinicoradiologic evidence of CNS involvement. RESULTS: We identified five CSF cytomorphologic patterns: (1) hemophagocytosis, (2) vacuolated macrophages without evidence of hemophagocytosis, (3) monocytes and/or nonvacuolated macrophages, (4) acellular specimens, and (5) bloody specimens. Patterns 1 and 2 were common in CNS-HLH and rare in patients without CNS involvement. The CSF cytomorphologic patterns did not correlate well with WBC counts or protein concentration. CONCLUSIONS: Our study offers a comprehensive view of the cytomorphologic features seen in CSF specimens from patients with HLH.

Central nervous system involvement in adults with haemophagocytic lymphohistiocytosis: a single-center study.

Hemophagocytic lymphohistiocytosis (HLH) is a rare multisystem disorder characterized by proliferation and diffuse infiltration multiple organs with histiocytes, including the central nervous system (CNS). Neurological manifestations of HLH have been recognized in different studies with children, but they remain relatively ill-defined in adults with HLH. From March 2008 to October 2014, 289 adult patients with HLH were admitted to our center. Clinical, radiological, and cerebral spinal fluid (CSF) data of the patients with CNS involvement were reviewed, and a retrospective study in our single-center was carried out. CNS involvement was observed in 29 patients (10%) either in their diagnosis process or during disease course. CNS symptoms included disturbance of consciousness, cranial nerve palsies, seizures, headache, limb paralysis, irritability, meningism, and memory loss. CSF analysis was conducted in 17 patients (59%). Among them, 11 patients (65%) were reported as having abnormal CSF. Neuroradiological studies were performed in 25 patients (86%). Among the 13 cases that underwent CT scan, one patient hemorrhaged. Single or multiple hypodense foci were detected in the other 2 patients. Magnetic resonance imaging (MRI) abnormalities were found in 15 patients, including focal lesions in cortical and adjacent subcortical regions with or without variable nodular or ring contrast-enhancement, multiple lesions in white matter, diffuse white matter signal changes, and meningeal enhancement. Basal ganglia, cerebellum, and brainstem lesions were also observed. CNS involvement could also be found in adult patients with HLH, but not as frequent as it was in children. The clinical manifestations could be diversified. By carrying out rigorous CNS examinations, an early diagnosis could be made and it was of the utmost importance for the prevention of further lesions.

Neurological presentation of hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is an inflammatory disorder arising from defects in critical regulatory pathways responsible for termination of inflammatory response. We are presenting a case report of a 20-year-old male, admitted to the Department of Neurology because of left lower limb weakness and balance disturbances. After a few days of hospitalization, fever occurred. Laboratory tests revealed anemia, neutropenia, lymphopenia, and thrombocytopenia. The clinical course and laboratory tests results confirmed the diagnosis of HLH. In our opinion, the disorder in the presented case occurred due to severe chronic active Epstein-Barr virus infection syndrome. We are presenting the case of pure neurological onset of hemophagocytic lymphohistiocytosis in an adult patient. Hemophagocytic lymphohistiocytosis, initially presenting with neurological symptoms, can occur in adult patients with irrelevant family history. It is a life-threatening but potentially curable condition requiring proper diagnostic and treatment management.

Extremely elevated cerebrospinal fluid protein levels in a child with neurologic symptoms: beware of haemophagocytic lymphohistiocytosis.

Neurologic symptoms can be the initial manifestation of haemophagocytic lymphohistiocytosis (HLH). In this case study, we present a 3-year old boy with a clinical picture of encephalitis, a cerebrospinal fluid (CSF) protein level up to 1165 mg/dl and diffuse cerebral MRI abnormalities. The diagnosis of HLH was established only 6 weeks after initial presentation. The boy recovered after HLH therapy with persisting mild cognitive defects. Genetic investigation demonstrated X-linked lymphoproliferative disease (XLP) as the underlying cause of HLH. The extremely elevated protein level in CSF in this case has not yet been reported in patients with HLH.

Central nervous system involvement in hemophagocytic lymphohistiocytosis: a single-center experience.

BACKGROUND: Hemophagocytic lymphohistiocytosis is a rare multisystem disorder characterized by proliferation and diffuse infiltration multiple organs with histiocytes, including the central nervous system. PATIENTS AND METHODS: Thirty children diagnosed with hemophagocytic lymphohistiocytosis between 1997 and 2010 were reviewed and analyzed. Central nervous system disease involvement was defined as the presence of neurological symptoms and signs or elevated values of cerebrospinal fluid cells and/or proteins. RESULTS: Among the 30 patients, 17 (56%) had central nervous system involvement. Fourteen patients (46%) presented with neurological symptoms including seizures, irritability, bulging fontanelle, cranial nerve palsy, or disturbance of consciousness, whereas the remaining three patients developed central nervous system symptoms during the course of the disease. Seventeen patients (56%) had cerebrospinal fluid abnormalities. Neuroradiological studies were performed in nine patients. The most common findings were edema, atrophy, subcortical necrosis, and high signal intensity on T2-weighted magnetic resonance imaging. All patients were treated according to the Hemophagocytic Lymphohistiocytosis-94 and Hemophagocytic Lymphohistiocytosis-2004 protocols. Patients with central nervous system involvement had greater mortality. In prediction of the outcome, the cutoff value for cerebrospinal fluid protein was 470 mg/L. The most common neurological sequela was psychomotor delay. CONCLUSION: Central nervous system involvement in hemophagocytic lymphohistiocytosis is common and is associated with poor outcome.

CNS involvement at the onset of primary hemophagocytic lymphohistiocytosis.

OBJECTIVES: To differentiate onset of CNS involvement in primary hemophagocytic lymphohistiocytosis (HLH) from that of other CNS inflammatory diseases and to identify early symptoms linked to abnormal cognitive outcome. METHODS: Forty-six children with primary HLH who had neurologic evaluation within 2 weeks and brain MRI within 6 months of diagnosis were included. Initial symptoms, CSF study, brain MRI, and neurologic outcome were assessed. Brain MRIs were compared with those of 44 children with acute disseminated encephalomyelitis (ADEM). RESULTS: At disease onset, 29 children (63%) had neurologic symptoms and 7 (15%) had microcephaly. Twenty-three (50%) children had abnormal CSF study, but only 15 (33%) had abnormal brain MRI. The latter showed that patients with HLH, unlike patients with ADEM, had symmetric periventricular lesions, without thalamic and brainstem involvement and with infrequent hyposignal intensity on T1. At the end of follow-up (3.6 ± 3.6 years), 17 of the 28 (61%) surviving patients had normal neurologic status, 5 (18%) had a severe neurologic outcome, and 6 (21%) had mild cognitive difficulties. Abnormal neurologic outcome was not influenced by age or type of genetic defect, but by the presence of neurologic symptoms, MRI lesions, or abnormal CSF study at onset. Early clinical and MRI symptoms may regress after treatment. CONCLUSION: Neurologic symptoms are frequent at the onset of primary HLH and are mostly associated with abnormal CSF findings, but with normal brain MRI. In cases of abnormal brain MRI, the observed lesions differ from those of ADEM.

Neonatal enteroviral sepsis/meningoencephalitis and hemophagocytic lymphohistiocytosis: diagnostic challenges.

We present the clinical course of three neonates with proven enteroviral infection and an initial clinical picture suggestive of hemophagocytic lymphohistiocytosis (HLH). After a complete workup, only one was treated for HLH. Of particular interest, the first newborn presented with hemophagocytic cells in the cerebrospinal fluid (CSF) and proved to have enteroviral meningoencephalitis but was ultimately not diagnosed with HLH. A fourth infant, who fulfilled the diagnostic criteria for HLH but did not have enteroviral infection, is included for comparison. We suggest that severe neonatal enteroviral infection and HLH are difficult to distinguish. Careful assessment is recommended, as prognosis and treatment differ between these two entities. Literature regarding neonatal enteroviral infection and HLH is reviewed, to demonstrate the continuum between the inflammation triggered by enteroviral infection and the occurrence of HLH, as well as their comparable CSF findings.

Frequency and development of CNS involvement in Chinese children with hemophagocytic lymphohistiocytosis.

BACKGROUND: We investigated the characteristics, frequency, and prognosis of central nervous system (CNS) involvement in patients with hemophagocytic lymphohistiocytosis (HLH). PROCEDURE: Neurological manifestations were prospectively assessed in 92 children with HLH treated from January 2004 to August 2008 at our center; 82 (89%) had associated viral infections (69 Epstein-Barr virus), one empyema, while no associated disease was identified in the remaining nine. Prior to treatment, all underwent cerebrospinal fluid (CSF) evaluation, brain computer tomography (CT) and/or magnetic resonance imaging (MRI). RESULTS: At diagnosis, 43 (47%) children had CNS involvement. Twelve patients (13%) had neurological symptoms, including seizures, ataxia, coma, cranial nerve palsy, and hemiplegia. All patients improved after 8 weeks of therapy, but one later developed progressive neurological symptoms and six discontinued therapy due to progressive systemic symptoms and/or other reasons. Fifteen patients had CSF abnormalities that all normalized completely after 6 weeks of treatment. Thirty-six patients (39%) had neuroradiological abnormalities; with 5 still under treatment, 15 lost to follow-up, and 16 followed after completion of therapy. Of these 16, 12 improved, 3 were unchanged, and 1 progressed. Among all 21 children with CNS involvement followed after completion of therapy, 10 recovered completely, 10 improved (3 had remaining neuroradiological abnormalities), and 1 progressed clinically and neuroradiologically. CONCLUSION: Most patients reported here suffered from secondary HLH and since CNS involvement is frequent in HLH, brain MRI at diagnosis is recommended in all HLH patients. Clinical and CSF abnormalities often improved within 8 weeks of therapy, but CT/MRI abnormalities normalized more slowly and less frequently.

Characterization of PRF1, STX11 and UNC13D genotype-phenotype correlations in familial hemophagocytic lymphohistiocytosis.

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare autosomal recessive lethal condition characterized by fever, cytopenia, hepatosplenomegaly and hemophagocytosis. The hallmark of FHL is defect apoptosis triggering and lymphocyte cellular cytotoxicity. Thus far three disease-causing genes (PRF1, UNC13D, STX11) have been identified. We performed a genotype-phenotype study in a large, multi-ethnic cohort of 76 FHL patients originating from 65 unrelated families. Biallelic mutations in PRF1, UNC13D and STX11 were demonstrated in 13/74 (18%), 6/61 (10%) and 14/70 (20%) patients, respectively. In 27/60 (45%) patients analyzed for all three genes, no molecular diagnosis was established. STX11 mutations were most common in Turkish families (7/28, 25%), whereas in Middle East families, PRF1 mutations were most frequent (6/13, 46%). No biallelic mutation was identified in most families of Nordic origin (13/14, 93%). Patients carrying PRF1 mutations had higher risk of early onset (age <6 months) compared to patients carrying STX11 mutations [adjusted odds ratio 8.23 (95% confidence interval [CI] = 1.20-56.40), P = 0.032]. Moreover, patients without identified mutations had increased risk of pathological cerebrospinal fluid (CSF) at diagnosis compared to patients with STX11 mutations [adjusted odds ratio 26.37 (CI = 1.90-366.82), P = 0.015]. These results indicate that the disease-causing mutations in FHL have different phenotypes with regard to ethnic origin, age at onset, and pathological CSF at diagnosis.

Frequency and spectrum of central nervous system involvement in 193 children with haemophagocytic lymphohistiocytosis.

Haemophagocytic lymphohistiocytosis (HLH) may cause meningoencephalitis and significant neurological sequelae. We examined the relationship between neurological symptoms and cerebrospinal fluid (CSF) at diagnosis, and long-term outcome, in all children enroled in the HLH-94-study prior to July 1, 2003, for whom information on CSF at diagnosis was available (n = 193). Patients were divided into four groups: (i) normal CSF (cells/protein) and no neurological symptoms (n = 71); (ii) normal CSF but neurological symptoms (n = 21); (iii) abnormal CSF but no symptoms (n = 50); and (iv) abnormal CSF with neurological symptoms (n = 51). At diagnosis, neurological symptoms were reported in 72/193 (37%) (seizures = 23); abnormal CSF in 101/193 (52%), and either or both in 122/193 (63%). Altogether 16/107 (15%) survivors had neurological sequelae at follow-up (median 5.3 years). Multivariate hazard ratios (HR) for mortality were 0.98 [95% confidence interval (CI) = 0.42-2.31], 1.52 (0.82-2.82) and 2.05 (1.13-3.72) for groups 2-4, compared with group 1. Moreover, sequelae were more frequent in group 4 (7/21, 33%) compared to groups 1-3 (9/86, 10%) (P = 0.015). Patients with abnormal CSF at diagnosis had significantly increased mortality [HR = 1.78 (95% CI = 1.08-2.92), P = 0.023]. Thus, a substantial proportion of HLH survivors suffer neurological sequelae, and children with abnormal CSF have increased risk of mortality and neurological sequelae. Prompt treatment of HLH at onset or relapse may reduce these complications.