COMPARATIVE STUDY OF FINE NEEDLE ASPIRATION CYTOLOGY, HISTOPATHOLOGY AND BACTERIOLOGY OF ENLARGED LYMPH-NODE
J G SALUJA, M S AJINYKA
Associate Professor and Head of Pathology Department at CMPH Medical College, Mumbai. and Mumbadevi Homeopathic Hospital, Vile-Parle, Mumbai 400 056.
150 cases of enlarged lymph node out of which 130 adult and 20 children were the material for study. All were screened for routine haematological test, Blood Glucose and HIV status.
Aspiration cytology result were very satisfactory with simultaneous smear study for AFB.
Results of FNAC were compared with Histopathology study, and the result obtained showed that histopathological picture like Non specific adenitis revealed AFB, in 33% of patients studied. Impression smear examination yielded best results, particularly in early cases. The Aspiration method of study is safe, reliable and cost effective procedure. The above mentioned procedures could prove useful in the peripheral hospitals where facilities are not available.
The disease known as tuberculosis is the reaction of the tissues of the human host to the presence and multiplication of mycobacteria tuberculosis.[1-8]
Therefore in describing the clinical states arising from the presence of organisms we are analysing a relationship which is the outcome on the one hand of the capacity of the host to contain and eliminate the organisms and, on the other hand, the organisms to multiply.
Wherever and whenever tubercle bacilli first lodge and begin to multiply in human tissues, the invasion begins a series of events related in time.
Some bacilli remain at the sight of entry and some are carried swiftly in the lymph flow to the nearest nodes. Multiplication then occurs in both places and the body responds so that tubercles develop.
In natural infection after about 4 to 8 weeks the body becomes sensitive to tubercle-protein and thereafter defence mechanism react more quickly. In most children or adults the natural defence processes are sufficient to contain and then slowly to heal the primary focus and regional nodes.
But disease can be progressive and either the primary focus or the nodes can enlarge to involve adjacent structures. Even when the focus or the nodes are apparently healed viable organisms may be present and give rise to disease after many years.
The diagnosis of TB continues to be surrounded by considerable uncertainty. Diagnosis is seldom confirmed by culture and usually relies on a constellation of symptoms, clinical sign, tuberculosis testing, X-ray chest. The diagnosis of tuberculosis lymphadenitis is mostly clinical and by histo-pathological evidence after surgical biopsy.
Fine needle aspiration cytology however canoften accurately diagnose in well-defined situation. This procedure is simple, non-traumatic and does not require anaesthesia. However, many other diseases like histoplasmosis, sarcoidosis, and lymphoma give rise to lymph node enlargement with similar histological findings. Sometimes it is essential to identify the causative organism for catching the diagnosis and treatment.
This study was undertaken to know the rational usefulness of fine needle aspiration technique for the said bacteriological examination by impression smear of lymph node and aspirates from clinically suspected cases of tuberculous lymphadenitis. An attempt is also made to correlate bacteriological results with cytopathology, histopathological findings.
MATERIAL AND METHOD
One hundred and fifty patients having lymphadenitis, by various out-patient departments of Mumbadevi Homoeopathic Hospital from 1995 to 1999 December formed the study material.
All the patients were evaluated clinically (Routine haematology study, blood sugar, HIV, mantoux test). Fine needle aspiration was then done as per the technique described by Orell et al using a 5 ml sterile syringe fitted with a 23 gauge needle, one and half inches long.
Smears were then made from the FNAC material and impression smear from the tissues and stained.
o Haematoxylin and eosin stain for cytological examination
o Ziehl Neelsen cold staining method the smear is air-dried and flame fixed. Then it is flooded with basic fuchin-phenol and allowed to stand for 10 minutes. Then it is counter stained by methylene blue for 2 minutes. The cold staining technique improves the positivity in the smear.
Children Family History (F/H) of T.B. Out of 20 cases only 8 were having F/H of T.B. Out of 20 cases only 6 were having exposure to T.B. patients.
Adults Past History (P/H) of T.B. Out of 130 cases 80 patients had history of T.B. in the past and 20 patients had exposure to T.B. patients.
Site in Children
2 matted lymph node in cervical region
6 single lymph node in cervical region
12 multiple lymph node in cervical region
Site in Adult
70 matted lymph node in cervical region
25 single lymph node in cervical region, axillary and discrete
28 multiple lymph node in cervical region, inguinal and general
150 cases were studied out of which 130 were adults and 20 were children. All were screened for routine haematological tests, blood sugar, HIV status and mantoux test.
In children mantoux test (Table 1) was positive in 75% cases, with 100% showing anaemia. 90% showed an increased E.S.R. One child tested HIV positive, his mother was also positive for HIV.
All the cases had mainly cervical lymphadenitis single or multiple, discrete or matted.
Among the 20 children studied (Table 3) 12 were diagnosed as nonspecific adenitis and 8 as tuberculous adenitis, 6 of these showed Acid fast bacilli in ZNFC stained (cold) smear examination. Of these 8 children diagnosed as T.B. adenitis, 6 were subjected biopsy and histopathology (Table 3) 5 of these showed granulomatous lesion and 1 showed non specific adenitis, 2 of the above patients showed AFB on smear.
Of the 12 children diagnosed as non specific adenitis 8 were biopsied and subjected to histopathology. 2 out this 8 also showed AFB on ZNFC staining (cold) of impression smear.
Table 1 MT Anaemia ESR(1hr) Blood sugar HIV +ve -ve +ve -ve 40-50mm 10-20mm +ve -ve +ve -ve Children 15 5 20 0 18 2 0 20 1 19 (8.0g-9.5g) Percentage 75% 100% 90% 0% 5% Comments Only fasting sugar done Mother HIV -ve confirmed by WB
TABLE 2 MT Anaemia ESR(1hr) Blood Sugar HIV +ve -ve 9.5-11.5g 12-15 40-50mm 30mm N IGT DM +ve -ve Adults 10 120 75 55 30 100 85 25 20 3 127 Percentage 7.69% 57.69% 76.92% 19% 16% 2.36% Comments N: Normal
IGT: Impaired glucose tolerance
DM: Diabetes melitus
Confirmed by WB
TABLE 3 ChildrenFNAC : 20 Patients Non specific lymphadenitis T.B. adenitis Smear (ZNCF) 6 12 8 30% 60% 40% Out of 12 Non-specific adenitis only 6 were positive for AFB on staining with ZNCF. Our of 8 T.B. Adenitis patients on FNAC only 6 were subjected to Histopathology Impression Smear (ZNCF) 2 1 5 33.3% 16.7% 83.3% 12 Non-specific Adenitis on FNAC out of which 8 were subjected to histopathology. Impression Smear (ZNCF) Non-Specific Adenitis 2 8 43.75% 100%
TABLE 4 AdultsFNAC : 130 Patients Non specific lymphadenitis T.B. adenitis Smear (ZNCF) 68 42 88 52.3% 32.3% 67.7% Histopathology : Out of 88 T.B. Adenitis (FNAC) 9 were subjected to Histopathology. Impression Smear (ZNCF) 6 3 6 66.7% 33.3% 66.7% 42 patients who were diagnosed as non-specific adenitis on FNAC only 12 were subjected to histopathology. Impression Smear (ZNCF) Non-Specific Adenitis 4 12 33.3% 100%
Fig 2 : FNAC
Fig 3 : Histopathology
NSLAd : Non specific Lymphadenitis
TB Ad : Tuberculosis adenitis.
In adult surprisingly (Table 2) only 10 cases showed mantoux test positive (7.69%). High ESR was seen in 30 cases and anaemia in 75 cases.
Diabetes mellitus was found in 20 cases and impaired glucose tolerance in 25 cases. HIV was confirmed in only 3 cases out of which the 130 adult patients studied 88 were diagnosed as tuberculous adenitis on FNAC (Table 4) 9 of these were subjected to biopsy and histopathology. Out of 88 cases on FNAC 68 cases showed Acid fast bacilli positive on smear.
Out of the 9 cases subjected to histopathology 6 showed granulomatous lesion and all showed Acid fast bacilli in ZNFC staining (cold) impression smear.
42 cases were diagnosed as nonspecific adenitis on FNAC, 12 of these cases were subjected to histopathology study. 4 out of these showed Acid fast bacilli positive on impression smear.
The Acid fast bacilli were seen even in patients who had histopathological picture like nonspecific adenitis in nearly 33% of patients studied.
Dependence on the clinical evidence alone would lead to erroneous diagnosis in considerable number of lymphadenitis cases. Hence we got an impetus to confirm the diagnosis by simple technique like FNAC or cytopathology or histopathology, along with bacteriological study.
Although histopathological study of the excised lymph node is diagnostic, but the disadvantages of this procedure are well known.
However we found fine needle aspiration cytology and the smear study is simpler, safe, cost effective and at the same time it suggests positive findings.
Similarly Blood Sugar investigation and HIV status was carried out. Only few (2.36%) patients were found to be HIV positive but it was essential for us to see whether these patients had any change of hyperplastic adenitis or caseous necrosis.
HIV positive patients are at increased risk of primary or reactivation of tuberculosis. T lymphocytes10 is the defence system in mycobacterium tuberculous infection which is the key mechanism of protection.
In HIV positive with tuberculosis produce decrease interferon as compared to lymphocyte of HIV negative individual with tuberculosis. Thus impaired T cell response in HIV positive individuals is the reason for their increased susceptibility to mycobacterium tuberculous infection.
Simultaneously (19%) of patients in adult were having impaired glucose tolerance and some were diabetic (16%) which favours the low susceptibility and impaired, humoral response in developing regional lymph node enlargement.
In children many were unaware of the lymph node enlargement, but positive history suggest that whenever resistance was lowered by secondary infection the prominence of lymph node was noticed by the parents.
Miller has already stated that the bacilli first lodge and begin to multiply in human tissue, the invasion begins a series of events related to time. Some bacilli remain at the site of entry and some are carried swiftly in the lymph flow to the nearest nodes. Multiplication occurs in both places and body responds so that tubercle develops. This stage is probably Stage 1 of Jone's and Campbell7,8 - the lymph nodes are firm, mobile, discrete, nontender showing non specific hyperplastic lymphadenitis.
In such situation when we carried out FNAC smear we found ZNFC cold staining technique revealed tubercle bacilli. This is probably due to the fact that lymph node being a site for immune response, keep the bacilli in a metabolically dormant state.
But in an HIV positive patient the smear revealed long beaded bacilli as compared to the others found in lymph nodes which were short and non beaded. Occurrence of lymphadenitis due to infection by mycobacterium other than typical one has been reported specially in immunocompromise individuals which may bring hurdles in the exact diagnosis of the disease. (D/D - nocardia infection, actinomycosis, histoplasmosis etc.)
Although in book on interpretation of lymph node biopsy G.R. Lathan has mentioned about the above results but the utility of the impression smear along with histopathology is not detected. We did not consider to carry out culture study because many a times the caseous material containing free fatty acid (FFA) inhibit the growth of mycobacterium tubercle and did not give good results in our cases.
Finally we would suggest that more and more cases should be screened with all three procedures where facilities are available, but in district hospitals and OPD impression smear and histopathology would be of immense value in diagnosing the disease without any delay.
ACKNOWLEDGEMENTWe thank the Dean Dr. SK Goel for permitting us to publish the hospital data. We express our gratitude to the staff of Pathology Department for the experimental work.
1.Kulkarni KS. Bacteriological study of tuberculous lymphadenitis. Ind J Tuberculosis 1974; XXI (2) : 61.
2.Christ ML, Felter KM. Fine needle aspiration cytology of toxoplasmic lymphadenitis. Acta Cytol 1982; 26 : 425.
3.Hooper AA. Tuberculous peripheral lymphadenitis. Brit J Surg 1972; 59 : 353.
4.Sing JP, Chathurvedi NK Das. Role of fine needle aspiration cytology in the diagnosis of tubercular lymph adenitis. Indian J Pathol and Microbiol 1989; 32 : 2.
5.Seth V, Kabra SK, et al. Tubercular lymphadenitis clinical manifestations. Indian J Pediatr 1995; 62 : 565.
6.Pamra SP, et al. Comparative study of tuberculous cervical lymph adenitis. Indian J Med Research 1974; 62 : 1631.
7.Lake SK, et al. Peripheral lymphadenopathy in childhood. Am J Dis Child 1974; 132 : 357.
8.Jones PG, Campbell. Tuberculous lymphadenitis in childhood. The significance of anonymous mycobacteria. Br J Surg 1962; 50 : 1-294.
9.Stanfield AG. (Ed). - Lymph node biopsy interpretation Churchill, Livingston, Edinburgh. 1985.
10.Khubchandani RP, Sainani GS. The HIV positive patient with tuberculosis. App J Medicine 1999; 25 (6) : 384.
11.Arora VK. Recent advance in Respiratory Medicine. 1997; 110.