Case Presentation

A 32-year-old Asian male, previously healthy, presented to the Accident & Emergency Department with a history of sudden onset of acute confusional state associated with fever, chills, and headache for the last 3 days. No history of loss of consciousness, seizures, sensory or motor loss, night sweats, abdominal pain, nausea or vomiting. He denied any history of previous similar episodes. There was no significant past medical, surgical, or family history.

On physical examination, the patient was febrile (low-grade fever with temperature of 38°C), yet hemodynamically stable. GCS was 10 out of 15. He was confused and not oriented to person, place, time and unable to obey one-step commands. Neurological examination showed reactive pupils bilaterally, positive neck stiffness, up-going plantar reflex on right side and proptosis of both eyes. Otherwise, rest of cranial nerves were intact with preserved gait, sensory & motor power in four limbs.

Investigations & Imaging findings

Basic laboratory and haematological findings revealed elevated white blood cell count (WBC = 24.3 x 103 uL), raised erythrocyte sedimentation rate (ESR = 41 mm/1hr) and C-reactive protein (CRP = 114.4 mg/L). Lumbar puncture was done and Cerebrospinal fluid (CSF) culture showed growth of Citrobacter Koseri, Pseudomonas Aeruginosa and Klebsiella Pneumoniae. Acid fast bacilli test was negative for Mycobacterium Tuberculosis infection.

Chest radiograph showed multiple lung nodules in lower zones of both lungs with prominent vessels shadows seen merging with them (Figure 1). Further evaluation with contrast-enhanced computerized tomography (CT) of the chest (Figure 2) revealed bilateral pulmonary AVMs.

In view of the patient’s neurological symptoms, contrast-enhanced CT scan of the brain was also performed and it revealed multiple, small, supra-tentorial, cerebral abscesses in the left frontal and right parieto-occipital lobes, associated with mild hydrocephalus. Abnormal leptomeningeal and ventricular wall enhancement was noted, consistent with meningitis and ventriculitis (Figure 3).

Throughout admission, the patient’s clinical condition deteriorated and a follow up contrast enhanced MRI study of the brain was done and it confirmed the CT brain findings (Figure 4). 

Treatment & Outcomes

In view of the patient clinical presentation, radiological and laboratory findings, the patient was admitted under the care of neurosurgical team and underwent insertion of external ventricular drainage through a burr hole. Patient was kept in intensive care unit and under air-born precautions. He completed a 6 weeks course of IV therapy of meropenem and vancomycin. Unfortunately, the patient continued to deteriorate clinically with persistent low GCS throughout admission and passed away.

Discussion

Hereditary Haemorrhagic Telangiectasia (HHT), or OslerWeber-Rendu disease, is a rare autosomal dominant multiorgan disorder. While it is a multi-system disease, it is mainly characterized by multiple arteriovenous malformations (AVMs) involving nasal cavity (90%), skin and mucosal membranes (90%), liver (30%), gastrointestinal tract (20%), pulmonary vasculature (50%) and CNS (5-10%) [1,2].

Healthy patients suddenly presenting with multiple cerebral abscesses and no previous history of an underlying cause should raise the suspicion of pulmonary AVMs. The abnormal pulmonary vasculature is known to cause cerebral abscesses which are serious neurological complications seen in up to 10% of these cases [3]. It is thought to be a result of paradoxical septic embolization passing through the abnormal arteriovenous fistulous communication and bypassing the pulmonary capillary bed and lodged in the greywhite matter junction of the brain parenchyma with subsequent cerebral abscess formation [1,4]. Therefore, brain abscess should be suspected in HHT patients presenting with neurological symptoms. Patient with HHT can also have other central nervous system involvement including cerebral ischemic infarction, cerebrovascular malformation (CVM), and metabolic disorders [2,5]. Trans-arterial vaso-occlusion is indicated in cases of PVAMs particularly those with feeding arteries exceeding 3mm in diameter as they are more likely to shower emboli [3].

Cross-sectional imaging with contrast-enhanced CT scans of the brain, chest and abdomen is the modality of choice in assessment of possible HHT to identify the vascular malformations. They would reveal the presence of visceral AVMs commonly involving the brain, lungs and liver [5]. The gold standard for diagnosis of PAVMs is by thin sections contrast enhanced CT of the chest which is superior to digital subtraction angiography due to its higher sensitivity and non-invasive nature [6]. CT of the chest also allows assessment of the diameter of the feeding arteries of these AVMs to correctly direct the clinicians to proper treatment [3]. Transthoracic contrast echocardiography is the screening test of choice for PAVMs; however, definite diagnosis of HHT will eventually require genetic testing for the responsible mutation [3,6]. 

Treatment of cerebral abscess is planned through multidisciplinary approach, involving both medical and surgical approach. It is generally recommended for the patient to undergo surgical drainage if the abscess measures > 2.5 cm in diameter, 6–8 weeks of intravenous antibiotic treatment, and to have serial imaging through CT or MRI every 15–20 days [7,8]. In our case, the patient’s diagnosis was delayed and was found to be complex with the presence of the AVMs. In addition to that, the patient’s poor clinical status did not allow for surgical drainage of the brain abscesses or to undergo pulmonary digital subtraction angiography of the PAVMs for diagnostic and therapeutic purposes to the possible underlying cause of the multiple abscesses.

In conclusion, HHT can cause radiological and treatment challenges, and knowledge of the pathology allows prompt diagnosis and management of its complications.

Learning points

1. HHT manifests as arteriovenous malformations in different parts of the body.
2. Radiology plays an important role in the diagnosis and management of HHT through image-guided endovascular therapy.
3. Undiagnosed cases of HHT may lead to high mortality and poor outcomes due to increased risk of embolic stroke and brain abscess, as presented in this case.

Figures

References

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