Early neurologic deterioration in intracerebral hemorrhage: Predictors and associated factors

OBJECTIVE

To identify potential predictors of and factors associated with early neurologic deterioration (END) in primary intracerebral hemorrhage (ICH).

METHODS

Two hundred sixty-six patients with spontaneous supratentorial ICH admitted within 12 hours of stroke onset were investigated in a multicenter, prospective study. Sixty-one clinical, biochemical, and neuroimaging variables were registered on admission, and 37 clinical and neuroimaging variables were registered at 48 hours. The volumes of the ICH and peripheral edema on admission and at 48 hours were measured on CT scan. Stroke severity and functional outcome were evaluated with the Canadian Stroke Scale (CSS) and modified Rankin Scale. END was diagnosed when the CSS score decreased > or =1 points between admission and 48 hours. With use of logistic regression analyses, baseline variables that predicted END and factors measured after the early acute phase and associated with END were investigated.

RESULTS

END occurred in 61 (22.9%) patients. Body temperature of >37.5 degrees C (odds ratio [OR] 24.5; 95% CI 4.8 to 125), neutrophil count (by 1,000-unit increase; OR 2.1; 95% CI 1.6 to 2.6), and serum fibrinogen levels of >523 mg/dL (OR 5.6; 95% CI 1.9 to 16.2) on admission were independent predictors of END. Among the factors recorded at 48 hours, early ICH growth (OR 4.3; 95% CI 1.3 to 14.5), intraventricular bleeding (OR 2.6; 95% CI 1.4 to 5.0), and highest systolic blood pressure (by 10-unit increase; OR 1.17; 95% CI 1.02 to 1.32) were associated with END in multivariate analyses.

CONCLUSIONS

Clinical and biologic markers of the inflammatory reaction on admission are predictors of subsequent END, whereas early ICH growth, intraventricular bleeding, and high systolic blood pressure within 48 hours are factors associated with END in patients with spontaneous ICH.

Molecular signatures of brain injury after intracerebral hemorrhage

BACKGROUND

The mechanisms of cellular death in the tissue surrounding an intracerebral hemorrhage (ICH) are not defined.

OBJECTIVE

To investigate the relationship of markers of excitotoxicity and inflammation to brain injury after ICH.

METHODS

A total of 124 consecutive patients with spontaneous ICH admitted within 24 hours of stroke onset were prospectively investigated. The volumes of the initial ICH, peripheral edema on days 3 to 4, and the residual cavity at 3 months were measured on CT scan. Glutamate, cytokines, and adhesion molecules were measured in blood samples obtained on admission. Stroke severity and neurologic outcome were evaluated with the Canadian Stroke Scale.

RESULTS

Poor neurologic outcome at 3 months (Canadian Stroke Scale < 7) was observed in 53 patients (43%). Stroke severity and glutamate concentrations (by each increment of 10 micromol/L, odds ratio 1.23; 95% CI 1.09 to 1.41), but not the initial volume of ICH, were independent predictors of poor outcome. In the multiple linear regression analyses, tumor necrosis factor-alpha concentration was correlated (r = 0.83, p < 0.0001) with the volume of perihematoma edema, and glutamate concentrations were correlated (r = 0.78, p < 0.0001) with the volume of the residual cavity. These same results were observed when lobar (n = 58) and deep (n = 66) ICH were analyzed separately.

CONCLUSIONS

High plasma levels of proinflammatory molecules within 24 hours of intracerebral hemorrhage onset are correlated with the magnitude of the subsequent perihematoma brain edema, whereas poor neurologic outcome and the volume of the residual cavity are related to increased plasma glutamate concentrations.

The clinical-DWI mismatch: a new diagnostic approach to the brain tissue at risk of infarction

OBJECTIVE

To evaluate the usefulness of a mismatch between the severity of acute clinical manifestations and the diffusion-weighted imaging (DWI) lesion in predicting early stroke outcome and infarct volume.

METHODS

One hundred sixty-six patients with a hemispheric ischemic stroke of <12 hours' duration were studied. The NIH Stroke Scale (NIHSS) score and the volume of DWI lesion were measured on admission and at 72 +/- 12 hours. Infarct volume was measured on T2-weighted or fluid-attenuated inversion recovery images at day 30. Early neurologic deterioration (END) was defined as an increase of > or =4 points between the two NIHSS evaluations. Thirty-eight patients received IV thrombolysis or abciximab. Clinical-DWI mismatch (CDM) was defined as NIHSS score of > or =8 and ischemic volume on DWI of < or =25 mL on admission. The adjusted influence of CDM on END, DWI lesion enlargement at 72 hours, and infarct growth at day 30 was evaluated by logistic regression analysis and generalized linear models.

RESULTS

CDM was found in 87 patients (52.4%). Patients with CDM had a higher risk of END than patients without CDM because NIHSS < 8 (odds ratio [OR], 9.0; 95% CI,1.9 to 42) or DWI lesion > 25 mL (OR, 2.0; 95% CI, 0.8 to 4.9). CDM was associated with an increase of 46 to 68 mL in the mean volume of DWI lesion enlargement and infarct growth in comparison with non-CDM. All the effects were even greater and significant in patients not treated with reperfusion therapies.

CONCLUSIONS

Acute stroke patients with an NIHSS score of > or =8 and DWI volume of < or =25 mL have a higher probability of infarct growth and early neurologic deterioration. The new concept of CDM may identify patients with tissue at risk of infarction for thrombolytic or neuroprotective drugs.

Evaluation of SPf66 malaria vaccine during a 22-month follow-up field trial in the Pacific coast of Colombia

A double-blind randomized placebo-controlled field trial with the SPf66 malaria vaccine was carried out in an endemic area consisting of 14 small villages with exclusive fluvial access, in a rain forest area along the Rosario River, Colombia. A total of 1257 subjects completed the full three dose vaccination schedule on days 0, 30 and 180 (643 vaccinated group/623 placebo group) and were followed-up by passive and active surveillance over a period of 22 months. One hundred and thirty-four Plasmodium falciparum malaria episodes were detected (53 in vaccinated group/81 in placebo group), yielding an attack rate of 5.47 cases/100 person years of follow-up (pyears) in the vaccine group and 8.44/100 pyears in the placebo group. The estimated vaccine protective efficacy was 35.2% (95% CI 8.4-54.2%, P = 0.01). This result supports earlier findings that the SPf66 malaria vaccine diminishes the risk of infection by P. falciparum in endemic areas of South America.

Access to Endovascular Treatment in Remote Areas

Background and Purpose—

Since demonstration of the benefit of endovascular treatment (EVT) in acute ischemic stroke patients with proximal arterial occlusion, stroke care systems need to be reorganized to deliver EVT in a timely and equitable way. We analyzed differences in the access to EVT by geographical areas in Catalonia, a territory with a highly decentralized stroke model.

Methods—

We studied 965 patients treated with EVT from a prospective multicenter population-based registry of stroke patients treated with reperfusion therapies in Catalonia, Spain (SONIIA). Three different areas were defined: (A) health areas primarily covered by Comprehensive Stroke Centers, (B) areas primarily covered by local stroke centers located less than hour away from a Comprehensive Stroke Center, and (C) areas primarily covered by local stroke centers located more than hour away from a Comprehensive Stroke Center. We compared the number of EVT×100 000 inhabitants/year and time from stroke onset to groin puncture between groups.

Results—

Baseline characteristics were similar between groups. Throughout the study period, there were significant differences in the population rates of EVT across geographical areas. EVT rates by 100 000 in 2015 were 10.5 in A area, 3.7 in B, and 2.7 in C. Time from symptom onset to groin puncture was 82 minutes longer in group B (312 minutes [245–435]) and 120 minutes longer in group C (350 minutes [284–408]) compared with group A (230 minutes [160–407]; P <0.001).

Conclusions—

Accessibility to EVT from remote areas is hampered by lower rate and longer time to treatment compared with areas covered directly by Comprehensive Stroke Centers.

Genetic control of the immune response to a synthetic vaccine against Plasmodium falciparum

Two independent vaccination trials using a hybrid synthetic polypeptide containing epitopes from four proteins of Plasmodium falciparum were performed. In the first trial 63 and in the second 122 volunteers were vaccinated, using different immunization schedules. The analysis of the humoral response to the vaccine, measured by IgG antibody titres to the polypeptide showed a bimodal distribution in both cases suggesting genetic control of the immune response to this protein. There was a small group of low or non-responders and a large group of good responders. HLA phenotyping of the two groups disclosed an association of the low responders to HLA-DR4 antigens with chi-square P value of 0.00039 when compared with the good responders group. These findings provide evidence for the genetic control of the immune response to the synthetic vaccine by the association of this response with particular alleles of the HLA class II antigens; such findings may lead to an explanation of the mechanism involved in disease susceptibility and need to be used in the design of a totally effective vaccine.

Tumor necrosis factor-alpha: a marker for peritoneal adhesion formation

This study investigates the possible correlation between higher levels of tumor necrosis factor-alpha (TNF-alpha) and higher rates of adhesion formation following standard bowel injury. Forty-five Sprague-Dawley rats were divided into three equal groups. Blood was obtained from all rats preoperatively. All rats were subjected to a laparotomy. In group 1 the peritoneal cavity was irrigated with normal saline. In group 2 the cecal serosa was abraded, while rats in group 3 had 2 cm of their small bowel resected. A peritoneal catheter was placed in all rats prior to closure. Blood samples were obtained at 30, 90, and 180 min following injury. Peritoneal exudate (PE) was collected and the catheter removed in 3 hr. Blood samples and peritoneal exudate were processed and levels of TNF-alpha were determined. The severity of adhesions was graded 3 weeks postoperatively using a score of 0 (absent) to III (extensive, dense). Histological evaluation for collagen deposition and fibroblasts was carried out. Rats in group 1 had significantly lower adhesion grades when compared to groups 2 and 3 (grade 0; P < 0.0001). Postoperatively, groups 2 and 3 had higher serum and PE TNF-alpha levels when compared with group 1 (P < 0.01). There was a significant correlation between higher grades of adhesions and higher levels of serum and PE at 30, 90, and 180 min following operation (P < 0.01 and < 0.05, respectively). TNF-alpha, a proinflammatory cytokine, appears to be a good biological marker for postoperative intraabdominal adhesion formation.

Calculi complicating a renal transplant

Four months after a cadaver kidney transplant, kidney stones were found in the renal allograft. Three major predisposing causes of nephrolithiasis were found in the patient, including hyperparathyroidism, renal tubular acidosis, and urinary tract infection. Hypercalcemia was corrected by parathyroidectomy. During the subsequent three years there was no enlargement of the renal stones and adequate kidney function was maintained. Renal tubular acidosis was not severe and seemed to be related to chronic rejection. Urinary tract infection was readily corrected with antibiotics and did not recur after the immediate post-transplant period. Surgical therapy for nephrolithiasis involving a kidney allograft was defferred since urinary flow was not obstructed. This course of management is recommended for use in patients with calculi complicating renal transplantation.

SPf66, a chemically synthesized subunit malaria vaccine, is safe and immunogenic in Tanzanians exposed to intense malaria transmission

As part of the first trial of the SPf66 malaria vaccine in Africa, three randomized double-blind placebo-controlled studies of SPf66 have been conducted in a highly endemic area of Tanzania. The objectives were to confirm that the product is immunogenic and safe in highly exposed individuals. Results from ten male adult expatriates indicated that the product used in Tanzania is at least as immunogenic as that used in Colombia. No major side-effects were observed in indigenous SPf66 recipients (18 adults, and 25 children aged 1-4 years). Anti-SPf66 antibody titres in all groups showed clear responses to three doses of the vaccine.

Atherosclerotic aortic arch plaques in cryptogenic stroke: a microembolic signal monitoring study

BACKGROUND AND PURPOSE

To find out the prevalence of relevant atherosclerotic plaques in the aortic arch and their potential role as a source of embolism in cryptogenic stroke.

METHODS

We performed a transoesophageal echocardiography (TEE) on 49 patients with cryptogenic stroke from a total series of 212 non-selected patients with acute ischaemic stroke studied prospectively by cranial computed tomography (CT), colour-duplex and transcranial Doppler (TCD) sonography with micro-embolic signal (MES) monitoring. Cryptogenic stroke was diagnosed in those patients without carotid or intracranial stenosis > 50%, nor lacunar or cardio-embolic strokes. We defined relevant plaques as those > or = 4 mm thick located in the ascending aorta or proximal arch.

RESULTS

Twenty-three patients (46.9%) had atherosclerotic aortic plaques (AAP): 3 in the ascending aorta (in 1 > or = 4 mm), 11 in the proximal aortic arch (in 4 > or = 4 mm) and 9 in the descending aorta (in 5 > or = 4 mm). Hence, 5 patients (10.2%) had relevant plaques. Aortic plaques were significantly related to older age (p < 0.001) and male gender (p = 0.042). A carotid artery stenosis < 50% was found in 39% of patients with AAP and in 8% of those without AAP (p = 0.009). MES were detected in 3 patients with plaques > or = 4 mm thick, but not in those without AAP or with AAP < 4 mm thick (p = 0.006).

CONCLUSION

Although few patients with cryptogenic stroke had relevant plaques in our non-selected population, our results support the hypothesis that relevant aortic plaques have embolic potential.

Live interactive broadcast of laparoscopic surgery via the Internet

BACKGROUND

For the first time in the history of communications, we conducted live interactive broadcasts through the Internet (on August 29, and September 3, 1996).

METHODS

Successful transmissions were performed from Pontiac, Michigan, to Laguna Hills, California, and Buenos Aires, Argentina, and participants actively interacted in audio and video formats in real time.

RESULTS

Video images were transmitted at a rate of 1-2 frame/s and displayed in a 320 x 240 window at the remote sites. The loss of audio packets averaged 17% with a delay of 0.5-2 s. The broadcasting computer station was also able to receive real-time video and sound from the distant computers, allowing complete interaction between both parties over the duration of each transmission session. Average broadcast time was 1. 5 h +/- 30 min, and the cost of each transmission was equal to that of a regular local phone call.

CONCLUSIONS

Videoconferencing via the Internet is a viable method for transmitting information in real time allowing surgeons worldwide to work together during surgical procedures.

Characterization of SPf(66)n: a chimeric molecule used as a malaria vaccine

SPf66 is a chemically synthesized 45 amino acid peptide derived from fractions of four different proteins of Plasmodium falciparum (83, 55 and 35 kDa and CS, the circumsporozoite protein) that elicits a protective immune response against malaria. In this paper we show the characterization of the SPf(66)n in batch 9 to be used in a field trial in young children at Ifakara in Tanzania. The analysis of SPf(66)n indicates that it is highly soluble in water and that the amino acid composition and sequence corresponds to that designed for the synthesis of the polypeptide. The packed product has a molecular weight ranging from 10 to 25 kDa. It is pure, free of metallic contaminants, atoxic and stable at 4 degrees C. The antibodies raised against this product in rabbits recognize the individual antigenic determinants of the molecule and the native epitopes of merozoites.

Predicting Motor Outcome in Acute Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Predicting motor outcome following intracerebral hemorrhage is challenging. We tested whether the combination of clinical scores and DTI-based assessment of corticospinal tract damage within the first 12 hours of symptom onset after intracerebral hemorrhage predicts motor outcome at 3 months.

MATERIALS AND METHODS

We prospectively studied patients with motor deficits secondary to primary intracerebral hemorrhage within the first 12 hours of symptom onset. Patients underwent multimodal MR imaging including DTI. We assessed intracerebral hemorrhage and perihematomal edema location and volume, and corticospinal tract involvement. The corticospinal tract was considered affected when the tractogram passed through the intracerebral hemorrhage or/and the perihematomal edema. We also calculated affected corticospinal tract-to-unaffected corticospinal tract ratios for fractional anisotropy, mean diffusivity, and axial and radial diffusivities. Motor impairment was graded by the motor subindex scores of the modified NIHSS. Motor outcome at 3 months was classified as good (modified NIHSS 0-3) or poor (modified NIHSS 4-8).

RESULTS

Of 62 patients, 43 were included. At admission, the median NIHSS score was 13 (interquartile range = 8-17), and the median modified NIHSS score was 5 (interquartile range = 2-8). At 3 months, 13 (30.23%) had poor motor outcome. Significant independent predictors of motor outcome were NIHSS and modified NIHSS at admission, posterior limb of the internal capsule involvement by intracerebral hemorrhage at admission, intracerebral hemorrhage volume at admission, 72-hour NIHSS, and 72-hour modified NIHSS. The sensitivity, specificity, and positive and negative predictive values for poor motor outcome at 3 months by a combined modified NIHSS of >6 and posterior limb of the internal capsule involvement in the first 12 hours from symptom onset were 84%, 79%, 65%, and 92%, respectively (area under the curve = 0.89; 95% CI, 0.78-1).

CONCLUSIONS

Combined assessment of motor function and posterior limb of the internal capsule damage during acute intracerebral hemorrhage accurately predicts motor outcome.

Laparoscopic appendectomy: a viable alternative approach

Laparoscopic appendectomy (LA) is relatively a new technique and requires comparison to open appendectomy (OA) to determine the more favorable approach in the surgical management of acute appendicitis. We designed this study to compare the course and postoperative complications between LA and OA. We reviewed the charts of both groups of patients and followed their course in the hospital. Seventy-seven patients who underwent LA with one conversion to the open technique (1.3%) were compared to 84 patients who underwent OA. There was no difference in age and sex distribution. The mean hospital stay was shorter in the LA (32.5+/-10 vs 74.2+/-24 h, p < 0.0001). Parenteral analgesia requirement was higher in the OA group (4.7+/-1.4 vs 2.6+/-2, p < 0.0001). The total cost was higher in the OA group ($11,260+/-4000 vs 7,090+/-3500, p < 0.05). There was no significant difference in the OR time, duration of the procedure, and surgery costs between both groups. Normal appendices removed were similar in both OA and LA groups (23.8 vs 28.9%). There was no difference in the rates of postoperative complications between both groups. We conclude that LA is a viable alternative to OA. It is safe, cost effective, and less invasive than the OA with less pain and shorter hospital stay.

How predictors and patterns of stroke recurrence after a TIA differ during the first year of follow-up

The highest risk of subsequent stroke after a TIA occurs within the first week after the index event. However, the risk of stroke recurrence (SR) remains high during the first year of follow-up. We studied the temporal pattern and predictors of SR (at 7 days and from 7 days to 1-year follow-up). Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We determined the short-term (at 7 days) and long-term (from 8 days to 1 year) risk of SR. Patients who underwent short-term recurrence and long-term recurrence were compared with regard to clinical findings, vascular territories, and etiology. Enough information (clinical variables and extracranial vascular imaging) was assessed in 1,137 (90.6 %) patients. The 7-day stroke risk was 2.6 %. 32 (3.0 %) patients had an SR after 7-day follow-up. Multiple TIA (HR 3.50, 1.67-7.35, p = 0.001) and large artery atherosclerosis (HR 2.51, 1.17-5.37, p = 0.018) were independent predictors of early SR, whereas previous stroke (HR 1.40, 1.03-1.92, p = 0.034) and coronary heart disease (2.65, 1.28-5.50, p = 0.009) were independent predictors of late SR. Notoriously, 80 % of SR happened in the same territory of the index TIA at 7-day follow-up, whereas only 38 % during the long-term follow-up (p < 0.001). Different predictors of SR were identified throughout the follow-up period. Moreover, the ischemic mechanism differed in early and late stroke recurrences.

Production and Characterization of Monoclonal Antibodies to E1 Tor Toxin Co-Regulated Pilus ofVibrio cholerae

Murine monoclonal antibodies (MAbs) against Vibrio cholerae toxin co-regulated pilus (TCP) were generated using conventional hybridoma procedures. Four hybridomas were obtained and two characterized. Hybridomas 10E10E1 and 4D6F9 secreted antibodies of the IgG2a and IgG1 isotypes, respectively, that reacted with a 24-kDa antigen corresponding to the product of the El Tor tcpA gene fused to a six Histidine tail. Additionally, MAbs produced by 4D6F9 selectively recognized the major pilin subunit (TcpA) of El Tor and O139 vibrios in western immunoblot, while MAbs from 10E10E1 also cross-reacted with classical TcpA. Furthermore, vibrios expressing TCP on their surface selectively inhibited binding of the antibodies secreted by both hybridomas to TcpA-coated microtiter plates. Thus, the MAbs reported in this work detected the structural subunit of the pilus either denatured or assembled on the bacterial surface.

Abstract WP372: The Acute ICH Growth Score: Simple and Accurate Predictor of Hematoma Expansion in Patients with Acute Intracerebral Hemorrhage

Background and Purpose: Acute intracerebral hemorrhage (ICH) hematoma expansion predicts high mortality and morbidity, occurring in a third of patients presenting with this condition. Recent studies correlated ultra-early hematoma growth and hematoma morphologic appearance with ICH expansion. Our purpose was to develop simple and clinically useful score that would predict ICH hematoma expansion accurately.

Methods: This cohort included patients with primary or anticoagulation-associated ICH patients presenting <6 hours post ictus prospectively enrolled in the PREDICT study. Patients underwent baseline CT, CT angiography and 24-hour CT for hematoma expansion analysis. A risk score model was developed for predicting hematoma expansion (> 6 ml or > 33%). A 7-point acute ICH growth score was based on ultra-early hematoma growth > 5 mL/hour (yes=1), irregular morphology (yes=1), density heterogeneity (yes=1), presence of fluid-blood levels (yes=1), spot sign (yes=1), and use of anticoagulation (yes=2). Discrimination of the expansion score was assessed.

Results: We retrospectively studied 301 primary or anticoagulation-associated intracerebral hemorrhage patients. The 7-point acute ICH growth score demonstrated good discrimination for hematoma expansion>6 mL or 33% (area under the curve of 0.76). Median and significant HE are shown in the table below (p<0.001).

Conclusions: In a multicenter prospective study, the ICH expansion score demonstrate good correlation with hematoma expansion, and included recently reported variables such as morphology and ultraearly growth.

In-flight continuous vital signs telemetry via the Internet

BACKGROUND

Current methods available to assess a passenger's life threatening medical condition during in-flight emergencies are inadequate. Critical communication channels between the airplane and ground control rely only on voice communication via a two-way radio. The purpose of this study was to test the efficacy of cellular telephone technology via the Internet as a cost-effective way to obtain the "linking" pathway from an aircraft to a ground medical facility by conducting a simulated on line triage.

METHODS

On July 31, 1997, we transmitted vital signs from a Boeing 757, flying from Chicago to Los Angeles, simultaneously to: The Saddle Back Memorial, in Laguna Hills, CA; Hospital Santojanni in Buenos Aires, Argentina; and the Medical Department of American Airlines in Dallas/Fort Worth, TX. Three lead EKG, heart rate, BP, arterial oxygen saturation, end tidal CO2, respiratory rate body temperature and real time video images were collected from a passenger and transmitted to each facility from the aircraft via the Internet. Access to the Internet was gained via the cellular phone aboard the aircraft.

RESULTS

A total of 20 different simulated scenarios of an medical emergency condition were successfully transmitted, simultaneously, to all health care facilities. All data was received without any corruption with an average delay time of 1 s.

CONCLUSIONS

Close monitoring of the patient can lead to a better understanding and assessment of a medical condition, improve in-flight patient care, accelerate the decision making process by making an early diagnosis, and correct a life-threatening condition before the patient arrives at the destination.

Arteriovenous fistula combined with basal external penile compression: a new cure for male impotence

We describe here a new procedure designed to enable reproducible sustained erection in a canine model. In 10 dogs, an end-to-side arteriovenous fistula was created between the inferior epigastric artery and deep dorsal vein. A chronic skin tunnel was created at the penile base. Blood flow, intracavernosal pressure and intraspongiosal pressure and blood gases were measured initially and 3 months later. Cuff application for 30 minutes was used daily. At 3 months, animals were sacrificed and biopsies obtained. Physiologic and histological parameters of erectile structures remained unchanged. Intracavernosal and intraspongiosal pressures increased to 33.7 +/- 6.7 mm Hg and 25.3 +/- 12.2 mm Hg (from 8.0 +/- 2.9 and 6.0 +/- 3.6 mm Hg) after cuff application. We conclude that sustained erections are feasible. This procedure appears safe for human trials.

[Hyperammonemic encephalopathy associated with valproate acid]

We report 4 clinical cases of hyperammonemic encephalopathy (HE) associated with valproate acid (VPA) and review the literature on its pathophysiology. In all four cases, hepatic function was normal and valproic levels were within the therapeutic range. Elevated ammonium levels were found as the only biochemical abnormality. Patients showed decreased level of consciousness, confusion, ataxia and seizures. In 1 case the EEG showed diffused triphasic waves with frontal predominance. After suppression of treatment with VPA there was remission of clinical manifestations, and ammonium levels returned to normal. In order to obtain the correct diagnosis of HE, in all patients treated with either VPA mono or polytherapy, ammonium levels should be considered.