Raimondi et al.13 The fixating tabs at both the ends prevented thetube from both migrating and kinking.

Unusual migration

Migration of shunts has been reported into various unusual sites.These include the cerebellum, ventricular system, subgaleal space,sphenoid sinus, heart, thorax, hollow abdominal viscus, pelvic vis-cera, scrotum and abdominal incisions and defects.6,7,9,11,14–17

However, in our third case, the LP shunt passed through the spinalSAS, into the IVth ventricle, through the foramen of Magendie,and penetrated the superior medullary velum to lie just posteriorto the pineal calcification in the quadrigeminal cistern. This unu-sual shunt migration has never been reported before. During shuntrevision, forced manipulation may have endangered vital struc-tures within and around the brainstem so the original, migratedshunt tube was left in situ.

To conclude, episodic increase in intra-abdominal pressure wasclosely related to the proximal migration of a unishunt system inour reported cases. Proximal migration into the quadrigeminal cis-tern through the IVth ventricle and the superior medullary velumhas not been previously reported.

ACKNOWLEDGEMENT

We gratefully acknowledge the kind help of Mr Bill Frew, Librar-ian, Foster Library, for his help with the scientific material andphotographs.

REFERENCES

1. Burgett RA, Purvin VA, Kawasaki A. Lumboperitoneal shunting forpseudotumor cerebri. Neurology 1997; 49: 734–739.

2. Suri A, Pandey P, Mehta VS. Subarachnoid hemorrhage and intracerebralhematoma following lumboperitoneal shunt for pseudotumor cerebri: a rarecomplication. Neurol India 2002; 50: 508–510.

3. Abou el Nasr HT. Modified method for prophylaxis against unishunt systemcomplications with presentation of total intraventricular migration of unisystemventriculoperitoneal shunt. Child's Nerv Syst 1998; 4: 116–118.

4. Yoshida S, Masunaga S, Hayase M, Oda Y. Migration of the shunt tube afterlumboperitoneal shunt - two case reports. Neurol Med Chir (Tokyo) 2000; 40:594–596.

5. Eljamel MS, Sharif S, Pidgeon CN. Total intraventricular migration ofunisystem venticulo-peritoneal shunt. Acta Neurochir (Wien) 1995; 136:217–218.

6. Alleyne CH, Shutter LA, Colohan AR. Cranial migration of a lumboperitonealshunt catheter. South Med J 1996; 89: 634–636.

7. Anthogalidis E-I, Sure U, Hellwig D, Bertalanffy H. Intracranial dislocation ofa lumboperitoneal shunt catheter: Case report and review of the literature. ClinNeurol Neurosurg 1999; 101: 203–206.

8. Carroll TA, Jakubowski J. Intrathecal migration of a lumboperitoneal shunt. BrJ Neurosurg 2000; 14: 496–497.

9. Satow T, Motoyama Y, Yamazoe N, Isaka F, Higuchi K, Nabeshima S.Migration of a lumboperitoneal shunt catheter into the spinal canal–Case report.Neurol Med Chir (Tokyo) 2001; 41: 97–99.

10. Henry-Feugeas MC, Idy-Peretti I, Blanchet B, Hassine D, Zannoli G,Schouman-Claeys E. Temporal and spatial assessment of normal cerebrospinalfluid dynamics with MR imaging. Magn Reson Imaging 1993; 11: 1107–1118.

11. Chan Y, Datta NN, Chan KY, Rehman SU, Poon CY, Kwok JC. Extrusion ofthe peritoneal catheter of a VP shunt system through a gastrostomy wound.Surg Neurol 2003; 60: 68–70.

12. Martinez-Lage JF, Poza M, Esteban JA. Mechanical complications of thereservoirs and flushing devices in the ventricular shunt systems. Br J Neurosurg1992; 6: 321–325.

13. Raimondi AJ, Robinson JS, Kuwamura K. Complications of ventriculo-peritoneal shunting and a critical comparison of the three-piece systems. Child'sBrain 1977; 3: 321–342.

14. Dominguez CJ, Tyagi A, Hall G, Timothy J, Chumas PD. Sub-galeal coiling ofthe proximal and distal components of a ventriculo-peritoneal shunt. Anunusual complication and proposed mechanism. Child's Nerv Syst 2000; 16:493–495.

15. Li KW, Ciceri E, Lasio G, Solero CL, DiMeco F. Shunt migration into thesphenoid sinus: case report. Neurosurgery 2003; 53: 441–443.

16. Rodriguez-Sanchez JA, Cabezudo-Artero JM, Porras Estrada LF. Unusualmigration of the distal catheter of a ventriculoperitoneal shunt into the heart:case report. Neurosurgery 2003; 52: 1510.

17. Wani AA, Ramzan A, Wani MA. Protrusion of a peritoneal catheter through theumbilicus: an unusual complication of a ventriculoperitoneal shunt. PediatrSurg Int 2002; 18: 171–172.

Isolated hypoglycorrachia:leptomeningealcarcinomatosis causingsubacute confusion

Peter Kim1MBBS(HONS)MBBS(HONS), David Ashton2

MBBSMBBS,

John D Pollard2PHD FRACPPHD FRACP

1Department of Neurology, Liverpool Hospital, 2Department of Neurology,

Royal Prince Alfred Hospital; Sydney, Australia

Summary We report a 76-year-old caucasian man who presented

with a 3-week history of progressive confusion. His past medical

history included a left nephro-uretectomy for poorly differentiated

transitional cell carcinoma 9 years previously. Besides his confusion,

his clinical and neurological examination was unremarkable. Exten-

sive investigation revealed only isolated hypoglycorrachia and mildly

elevated CSF protein. Cerebral CT and MRI scans without contrast

did not reveal any abnormalities. As his condition continued to

decline, an MRI scan of the brain with gadolinium was performed

which revealed extensive nodular enhancement of the surface of the

cerebellum and brainstem and both temporal lobe convexities.

Repeat lumbar puncture showed malignant cells in the CSF and

confirmed the diagnosis of leptomeningeal carcinomatosis. This

case illustrates that leptomeningeal carcinomatosis should be con-

sidered in the differential diagnosis of cognitive decline in the elderly,

after other common aetiologies have been excluded. The index of

suspicion should be increased in patients with a prior history of

cancer.

ª 2005 Elsevier Ltd. All rights reserved.

Journal of Clinical Neuroscience (2005) 12(7), 841–843

0967-5868/$ - see front matter ª 2005 Elsevier Ltd. All rights reserved.

doi:10.1016/j.jocn.2004.11.007

Keywords: hypoglycorrachia, leptomeningeal carcinomatosis,

confusion

Received 5 July 2004

Accepted 15 November 2004

Correspondence to: Dr. Peter Kim, Department of Neurology, Liverpool

Hospital, Locked bag 7103, Liverpool BC, NSW 1871, Australia.

Tel.: +61 2 9828 3646; Fax: +61 2 9828 3846;

E-mail: peterkim76@hotmail.com

INTRODUCTION

Leptomeningeal carcinomatosis (LC) was first reported in 1970and occurs most commonly in adults with a history of breast carci-noma, lung carcinoma and melanoma.1,2,3 LC has been reported tooccur in 2 to 25% of patients with malignancy and typically has apoor prognosis even with aggressive treatment.2,3

We present a case of LC in an elderly patient where the onlypresenting symptom was cognitive decline associated with iso-lated hypoglycorrachia as the only CSF abnormality.

ª 2005 Elsevier Ltd. All rights reserved. Journal of Clinical Neuroscience (2005) 12(7)

841Hypoglycorrachia and leptomeningeal carcinomatosis

CASE REPORT

A 76-year old caucasian man presented with a 3-week history ofprogressive confusion. He was previously living independentlywith normal premorbid cognitive function. His past medical his-tory included a left nephro-uretectomy for poorly differentiatedtransitional cell carcinoma 9 years previously. He also had hyper-tension, hypercholesterolaemia and gastro-oesophageal reflux. Hismedications included omeprazole, telmisartan and simvastatin. Hedid not consume alcohol or smoke.

On examination, he was alert and able to follow simple com-mands. He was afebrile and had no nuchal rigidity. He was notoriented to time or place and his concentration and memory weregrossly impaired. His general examination was unremarkable andneurological examination was normal, including fundoscopy, cra-nial nerve, upper and lower limb examination and cerebellar andsphincter examinations.

Full blood count, serum electrolytes, urea and creatinine, cal-cium, erythrocyte sedimentation rate, and arterial blood gaseswere normal. Chest X-ray, blood and urine cultures were normal.Vitamin B12, folate, thyroid function tests, angiotensin convertingenzyme (ACE) levels, human immunodeficiency virus (HIV) andsyphilis serology were unremarkable. An electroencephalogramwas performed and consistent with a moderate generalisedencephalopathy. A head CT was initially performed and was nor-mal and a subsequent MRI of the brain without gadolinium did notreveal any abnormalities.

Lumbar puncture and CSF examination showed a normal whitecell count but mildly raised protein at 0.59 g/L (normal: 0.15–0.45g/L). CSF glucose was markedly decreased (hypoglycorrachia) at1.2 mmol/L (normal: 2.5–5.0 mmol/L) with a concurrent serumglucose of 5.6 mmol/L. PCR of CSF for herpes simplex virusand mycobacterium tuberculosis were negative and viral and bac-terial cultures did not grow any organisms. Cytology did not re-veal any malignant cells.

As his condition progressively declined, an MRI of the brainwas repeated with gadolinium and this revealed extensive nodularenhancement of the cerebellar and brain stem surfaces and bothtemporal lobe convexities. (Figure 1, 2). Repeat lumbar puncturerevealed a CSF glucose of 1.6 mmol/L and a normal CSF whitecell count of 3 · 106/L. Cytology on the second specimen showedmalignant cells and was diagnostic of metastatic carcinoma. Therewere no skin lesions and ear/nose/throat examination did notreveal a primary lesion. A CT scan of the chest, abdomen andpelvis was normal. The patient was referred to palliative care

services as aggressive treatment was not considered appropriateand he died one month later.

DISCUSSION

Patients with LC present with a wide variety of symptoms and focalneurological deficits secondary to the effects of the tumour on nerveroots, direct extension into neural tissue or CSF obstruction.2,3 Thispatient is unusual in that the only presenting symptom of LC was adecline in cognitive function with no other evidence of tumourrecurrence or focal neurological signs.4 Furthermore, this case illus-trates that in the elderly, confusion or cognitive decline may be theonly presenting feature of LC, making diagnosis difficult.

Initial CSF examination showed marked hypoglycorrachia andmildly elevated protein with an absence of cells. Although hypo-glycorrachia in LC is recognised, it can also occur in viral, bacte-rial and fungal infections of the central nervous system (CNS).6,7

However, CNS infections are almost invariably associated withmarkedly elevated CSF protein and leucocytosis. An isolated find-ing of hypoglycorrachia would be highly unusual.

Jann et al5 suggested that hypoglycorrhachia in LC is not due toincreased utilisation of glucose by malignant cells but rather sec-ondary to abnormal blood to CSF glucose transport.

Our patient had a history of poorly differentiated transitionalcell carcinoma approximately 9 years previously, and extensiveinvestigation did not reveal another primary lesion. Coslettet al8 reported a case of LC with no other evidence of tumour,occurring 21 years following lobectomy for broncho-alveolarcarcinoma. Interestingly, in their patient, hypoglycorrachia wasalso the only initial abnormality.

Fig. 1 Axial T1-weighted MRI with gadolinium demonstrating diffuse

enhancement of the leptomeninges over the surface of the cerebellum and

brainstem.

Fig. 2 A. Sagittal T1-weighted MRI without (a) and with (b) contrast. The

unenhanced scan did not demonstrate the abnormality. After administration of

gadolinium diffuse enhancement over the cerebellar folia, tentorium cerebelli

and brainstem, often referred to as ‘zuckerguss’ or sugar icing, was seen.

Journal of Clinical Neuroscience (2005) 12(7) ª 2005 Elsevier Ltd. All rights reserved.

842 Kim et al.

Diagnosis of LC in our patient was suggested by contrast en-hanced MRI of the brain and confirmed on repeat CSF cytologicalexamination. It is important to note that multiple specimens maybe required for cytological diagnosis as sensitivity is approxi-mately 50 to 60% with a single sample and up to 90% after 3 con-secutive lumbar punctures.9

This case demonstrates that cerebral CT and MRI without con-trast is suboptimal for the detection of LC. Contrast enhanced T1-weighted MRI scan is the imaging modality of choice in suspectedneoplastic leptomeningeal disease.10

The diagnosis of LC was important in this patient's managementas it prevented unnecessary invasive testing, allowed explanationand planning for the family, and enabled early referral to appropri-ate palliative care services.

This case illustrates that LC should be considered in the differ-ential diagnosis of isolated cognitive decline in the elderly, afterother common aetiologies have been excluded. Results of CSFexamination may be subtle and include hypoglycorrachia withoutan elevation of white cell count. The index of suspicion for LCshould be raised in patients with prior history of cancer.

REFERENCES

1. Noel G, Proudhom M-A, Valery C-A, et al. Radiosurgery for re-irradiation ofbrain metastases: results in 54 patients. Radiother Oncol 2001; 60: 61–67.

2. Chamberlain MC. Leptomeningeal metastases. J Neurooncol 1998; 37:271–284.

3. Balm M, Hammack J. Leptomeningeal carcinomatosis. Presenting features andprognosis. Arch Neurol 1996; 53: 626–632.

4. Trivedi RA, Nichols P, Coley S, et al. Leptomeningeal glioblastoma presentingwith multiple cranial neuropathies and confusion. Clin Neurol Neurosurg 2000;102: 223–226.

5. Jann S, Comini A, Pelligrini G. Hypoglycorrachia in leptomeningealcarcinomatosis. A pathophysiological study. Ital J Neurol Sci 1988; 9: 83–88.

6. Casado JL, Quereda C, Olivia J, et al. Candidal meningitis in HIV-infectedpatients: analysis of 14 cases. Clin Infect Dis 1997; 25: 673–676.

7. Leonard JM. Cerebrospinal fluid formula in patients with central nervoussystem infection. Neurol Clin 1986; 4: 3–12.

8. Coslett HB, Teja K, Sutula TP. Meningeal carcinomatosis 21 years followingbronchiolo-alveolar carcinoma: diagnosis by cisternal CSF examination.Cancer 1982; 49: 173–176.

9. Van Oostenbrugge RJ, Twijnstra A. Presenting features and value of diagnosticprocedures in leptomeningeal metastases. Neurology 1999; 53: 382–385.

10. Singh SK, Leeds NE, Ginsberg LE. MR imaging of leptomeningeal metastases:comparison of three sequences. AJNR Am J Neuroradiol 2002; 23: 817–821.

ª 2005 Elsevier Ltd. All rights reserved. Journal of Clinical Neuroscience (2005) 12(7)

843Hypoglycorrachia and leptomeningeal carcinomatosis