Harries, AD

Macheso, A

Reeve, PA

Wirima, JJ

English

AJOL - African Journals Online

Lumbar puncture in acute admissions to an adult medical ward A. D. Harries, et al Introduction Lumbar puncture has been used in clinical medicine for 90 years. There are three main indications: (i) for diagnostic purposes Table I; (ii) for introducing contrast media; and (iii) for introducing chemotherapeutic agents, for example, in leukaemia. Acute adult admissions to our wards will usually have a lumbar puncture if there is a suspicion of meningitis or subarach-noid haemorrhage provided there is no contra-indication such as papilloedema. Clinical features which suggest these two diagnoses include fever, headache, vomiting, convulsions, neck stiffness and altered conciousness. Other diseases, however, can be associated with similar symptoms and signs, and the present study was performed to determine the spectrum of diag-noses among patients in whom lumbar puncture is considered necessary. Table I INDICATIONS FOR PERFORMING LUMBAR PUNCTURE FOR DIAGNOSIS I. Suspected subarachnoid haemorrhage 2. Infections of central nervous system (viral, bacterial, tuberculous, fungal and protozoal meningitis; neurosyphilis; acute and suba-cute encephalitides). 3. Selected strokes, but not routinely. 4. Peripheral neuropathies - ego Guillain -Barre Syndrome. 5. Suspected multiple sclerosis - very rare in Africa. Methods From January t6 June 1986, 1,908 patients were admitted to the adult medical wards, Kamuzu Central Hospital, Lilongwe. Lumbar puncture was considered necessary in 15 I, patients because of a clinical suspicion' of meningitis or subarachnoid haemorrhage. A record was made of clinical features on admis-sion, cerebrospinal fluid (CSF) fin'dings, final diagnosis and whether the patient recovered or died. Patients with bacterial meningitis were A. D. Harries, Medical Specialist. A. Macheso, Clinical Officer. P. A. Reeve, Medical Specialist. J. J. Wirima. Principal Medical Specialist. Department of Medicine. Kamuzu Central Hospital. Lilongwe. treated with parenteral penicillin and chloram-phenicol which in survivors was continued for 14 days. Patients with tuberculous meningitis were treated with streptomycin, rifampicin, isoniazid, pyrazinamide and corticosteroids. Patients with subarachnoid haemorrhage often received dexamethasone in an attempt to reduce cerebral oedema and antihypertensives to reduce high elevations of blood pressure. Patients with other diagnoses were treated along usual lines. Results Unsuccessful Lumbar Puncture Lumbar puncture was unsuccessful in 6 patients, a failure rate of 4%. Diagnoses were; drug overdose, psychosis, epilepsy, acute bacillary dysentery, tetanus and meningitis. The patient with tetanus died, the others recovered. The patient with suspected meningitis was treated successfully with antibiotics for 14 days. CSF Findings Lumbar puncture was carried out successfully in 145 patients. There were 84 men and 61 women, mean age 30 (range 13-60) years. a) Bacterial Meningitis Bacterial meningitis was diagnosed in 43 patients. CSF was cloudy in appearance in 40 and clear in 3. In 36 patients microscopy revealed a mean white cell count of 1546/mm3 (93% polymorphonuclear leucocytes); in the remainder white cells were too innumerable for counting, although in all cases polymorpho-nuclear leucocytes exceeded 90% of the total. CSF protein ranged from 78-1700 (mean 422) mg/dl. In 20 patients CSF glucose was zero. Organisms found by gram stain and/or culture were Spneumoniae(lO) N. menirigitidis(4), and Enterobacter species (l ).- In 20 patients no organism was isolated; 9 had' a history of antibiotic administration prior to hospital admission. ' b) Tuberculoqs Meni~gitis ,- . This diagnosis was made in three patients. cSywJ:i cloudy in"cJrte. and ,clear in two. Mean CSF white cell count -was 390/mm3 (75% lymphocytes). CSF protein ranged from 275-1200 '(mean 340) mg/dl and CSF glucose was zero in 2. c) Subarachnoid Haemorrhage Subarachnoid haemorrhage was present in 41 Reproduced  by Sabinet Gateway under licence granted by the Publisher ( dated 2012)eleven patients, the diagnosis based on uniformly blood stained CSF ± xanthochromic supernat-ant. d) Other In 88 patients CSF was clear (includes slightly hazy CSF in 7 from traumatic lumbar puncture), and microscopy revealed less than 5 WBC/mm 3 • In 5 patients CSF protein was greater than 40 mg/dl. Clinical Features and Outcome' Clinical features and outcome in the 4 groups of patients are in Table 2. In patients with bacterial meningitis the level of consciousness on admission was inversely related to mortality; there were no deaths in those who were alert, 8 deaths (42%) in those obtunded, and 9 deaths (53%) in those who were admitted unconcious. Of patients with bacterial meningitis who re-covered 5 had residual neurological deficits; VIII nerve deafness (3), VI nerve palsy (I), and right hemiparesis (l). In patients with subarachnoid haemorrhage 4 (67%) of those admitted uncon-cious died. The principal diagnoses of patients with normal CSF are in Table 3. 43 (84%) of 51 patients with enteric fever, malaria and pneu-monia had a fever (temperature greater than 37"C) on admission in contrast to one patient (l0%) with a diagnosis of cerebrovascular disease. Discussion Lumbar punctures are usually carried out by clinical officers or medical assistants whenever they suspect meningitis or subarachnoid hae-morrhage. Results indicate that these health workers are adept and competent at the proce-dure. Failed lumbar punctures were usually in uncooperative patients. Lumbar puncture in patients with tetanus is usually impossible because of rigidity of dorso-Iumbar musculature. 57 (39%) of 145 patients in whom CSF was obtained had meningitis or subarachnoid hae-morrhage. In bacterial meningitis visual inspec-tion of CSF established the diagnosis in most cases, and this allowed treatment to be promptly commenced. In 3 patients, however, CSF was clear and the diagnosis was dependent on microscopy. It is very important to examine a drop of clear CSF as soon as possible under the micrsocope at x40 power. More than 5 white cells/mm3, particularly if polYTlJorphonuclear leucocytes, should suggest meningitis. Although most patients with meningitis had fever and neck stiffness this was not a universal finding. Two case histories illustrate an import-ant point. Both patients were men and both were admitted unconcious. In one patient there was a history from the guardian of excess alcohol consumption the day before admission, and the breath of the other patient smelt strongly of alcohol. There was no fever and no neck stiffness in either patient. Blood glucose levels were low TABLE 2 CLINICAL FEATURES AND OUTCOME IN PATIENTS UNDERGOING SUCCESSFUL LUMBAR PUNCTURE Number Male: Female Age (range) in years Documented History Headache (%) Vomiting (%) Convulsions (%) Concious level Alert (%) Obtunded± 19(44) Confused Unconcious (%) Neck stiffness (%) Fever> 37"C (%) Recovered (%) Died (%) BACTERIAL TUBERCULOUS SUBARACHNOID OTHER MENINGITIS MENINGITIS HAEMORRHAGE 43 21:22 24(13-60) 39 30(77) 5(13) 2(5) 7(16) 19(44) 17(40) 36(84) 33(77) 26(60) 17(40) 3 2:1 36(28-40) 3 3 o o 3 2 11 8:3 38(20-60) 7 7(100) 4(57) 0 1(9) 4(36) 6(55) 7(64) 2(18) 5(45) 6(55) 88 53:35 30(17-60) 86 46(53) 5(6) 15(17) 32(36) 42(48) 14(16) 38(43) 51(58) 61(69) 27(31 ) Reproduced  by Sabinet Gateway under licence granted by the Publisher ( dated 2012)TABLE 3 DIAGNOSES IN PATIENTS WITH NORMAL CSF. Neck Elevated Number Stiffness(% ) CSF protein Death(%) x Typhoid Fever 21 7(33) 2 7(33) t Malaria 19 9(47) 2 0 Pneumonia II 9(82) 0 3(27) Cerebrovascular 10 4(40) 9(90) Disease # Miscellaneous 27 9(33) 0 8(30) x Diagnosis based on clinical features, normal or low WBC, response to chloramphenicol, or blood culture (one patient). t Blood film positive in 10 patients for P. Jalciparum; in 9 patients diagnosis on clinical grounds. # Includes tetanus, drug overdose, acute alcoholism, cervical spine problems, acute hepatic failure etc. at less than 40 mgldl, but there was no improvement in concious level after 50 ml of 50% glucose given intravenously. Lumbar puncture in both patients yielded cloudy CSF; s.pneumoniae was isolated in one and in the other gram stain and culture were negative. A high index of suspicion is needed if meningitis is not to be missed. In patients with clinical features suspicious of meningitis but in whom CSF was normal, typhoid fever, malaria, and pneumonia were important diagnoses to be considered, parti-cularly if there was fever. Several patients with pneumonia had normal chest findings on the day of admission, but developed signs 24-36 hours later. Neck stiffness in these patients results from meningism, which may also give rise to a positive Kerning's sign. Raised CSF protein with increased white cells may be found in typhoid fever<,} and malaria(2). It has been suggested that lumbar puncture in patients with a history of worsening headache, altered conciousness, focal neurology or papil-loedema is potentially hazardous and should be preceeded by CT scan,(3),(4). However, in bacterial meningitis a reduced level of concious-ness is common and neurological signs can be found in 50% of patients(5). Experienced health workers in Africa recommend that if there is a strong suspicion of meningitis or subarachnoid haemorrhage, both of which may be associated with mild papilloedema, lumbar puncture should still be done, if possible under cover of intravenous dexamethasone to prevent a tento-rial pressure cone(6). In our patients bacterial meningitis is common and it is eminently treatable provided chemo-. therapy is commenct;d early enough. In any patient suspected of having meningitis lumbar puncture is an essential investigation, and one which should be done as soon as possible. Acknowledgement We thank all the clinical officers, medical assistants and students who performed these lumbar punctures while on our wards. References (I) Parry E.H.O. (1984) Principles of Medicine in Africa. Second Edition. Oxford University Press. P. 274. (2) BeIlD.(I981) Lecture Notes in Tropical Medicine. Blackwell Scientific Publications Oxford. P. 1-31. (3) Duffy D.P. (1969) Lumbar puncture in the PJt'sence of Raised Intracranial Pressure. .,: BR. Med. J. i 407-409. (4) Richards P.G. Town Aghantse E. (1986) Dangers of Lumbar Puncture BR. Med. J. 292 605-606. (5) Van Voris L.P. Roberts N.J. (1983) Central Nervous System Infections in A Practical Approach to Infectious Diseases Ed. Reese R.E. and Gordon Douglas R. Little, Brown and Co. Boston/Toronto P. 269-276. (6) Bahemuka M. White N.J. Warrell D.A. Osuntokun B.O. Edoo B.B. (1984) The Nervous System in Principles of Medicine in Africa. Second Edition. Oxford University Press P. 577. Reproduced  by Sabinet Gateway under licence granted by the Publisher ( dated 2012)

Lumbar puncture in acute admissions to an adult medical ward

https://www.ajol.info/index.php/mmj/article/download/110952/100712

Lumbar puncture in acute admissions to an adult medical ward

Abstract

Similar works

Full text

Available Versions

AJOL - African Journals Online