Fine Needle Aspiration Cytopathology of Pediatric Lympha denopathy among Sudanese Children

Pediatric lymphadenopathy is a difficult medical condition that is frequently seen in children. Although the majority of these masses will be benign the fear of malignancy is ever present. Seeing the pediatric patient with enlarged lymph nodes can be quite a challenge not only because there is an extensive differential diagnosis but also because it’s never clear exactly when to offer an FNA or surgery for biopsy and culture (Zeharia et al., 2008). Cervical lymphadenopathy most commonly represents a transient response to a benign local or generalized infection, but occasionally it might herald the presence of a more serious disorder such as malignancy. Acute bilateral cervical lymphadenopathy usually is caused by a viral upper respiratory tract infection or bacterial pharyngitis. Acute unilateral cervical lymphadenitis is caused by streptococcal or staphylococcal infection in 40% to 80% of cases. The most common causes of subacute or chronic lymphadenitis are mycobacterial infection, cat scratch disease, and toxoplasmosis. Supraclavicular or posterior cervical lymphadenopathy carries a much higher risk for malignancies than does anterior cervical


Introduction
Pediatric lymphadenopathy is a difficult medical condition that is frequently seen in children.Although the majority of these masses will be benign the fear of malignancy is ever present.Seeing the pediatric patient with enlarged lymph nodes can be quite a challenge not only because there is an extensive differential diagnosis but also because it's never clear exactly when to offer an FNA or surgery for biopsy and culture (Zeharia et al., 2008).
Cervical lymphadenopathy most commonly represents a transient response to a benign local or generalized infection, but occasionally it might herald the presence of a more serious disorder such as malignancy.Acute bilateral cervical lymphadenopathy usually is caused by a viral upper respiratory tract infection or bacterial pharyngitis.Acute unilateral cervical lymphadenitis is caused by streptococcal or staphylococcal infection in 40% to 80% of cases.The most common causes of subacute or chronic lymphadenitis are mycobacterial infection, cat scratch disease, and toxoplasmosis.Supraclavicular or posterior cervical lymphadenopathy carries a much higher risk for malignancies than does anterior cervical
Examining the lymph nodes is an important aspect of the general physical examination of both well and ill children and adolescents.Lymph nodes are normal structures, and certain lymph nodes may be palpable in a healthy patient, particularly in a young child.Conversely, the presence of abnormally enlarged lymph nodes ("lymphadenopathy") can be a clue to a serious underlying systemic disease, and the differential diagnosis of lymphadenopathy can be broad.Thus, the challenge for the general pediatrician is to learn how to distinguish pathologic from nonpathologic lymph nodes and to develop a rational approach to the evaluation of lymphadenopathy.Because of its association with malignancy, lymphadenopathy can be a major source of parental anxiety.Therefore, it is crucial to know when to provide reassurance and to recognize when concern is sufficient to warrant referral to a subspecialist (Alison, 2008).
Pediatric tumors differ markedly from adult tumors in their nature, distribution, and prognosis.Fine Needle Aspiration Cytology (FNAC), a well established technique in adult oncology, is now being increasingly applied to childhood tumors as it permits a rapid diagnosis with minimal trauma, morbidity, and a low complication rate.FNAC is thus an effective method for evaluation of masses in pediatric patients.It need not replace the open surgical biopsy, but can be a valuable tool for screening of palpable as well as nonpalpable masses, and for follow up of patients with a history of malignancy (Maheshwari et al., 2008).For its diagnostic potential to be realized however, the clinician must understand the strengths and weaknesses of this procedure, along with the technical limitations.Therefore, the aim of this study was find out the common causes of pediatric lymphadenopathy in Sudan by FNAC, which is commonly practiced procedure, in such conditions.

Materials and Methods
In this study is a descriptive prospective study conducted on consecutive 100 pediatric patients (age, 2 to 14 years) who referred for FNAC of an enlarged peripheral lymph node.Patients were included if FNAC of a peripheral lymph node has been required as an initial diagnostic test.Patients were randomly selected from different pediatric clinics in Khartoum city.
FNACs of palpable masses were performed by a pathologist and pediatric surgon according to a standard procedure.The overlying skin was cleaned with ethanol and, if necessary, nesthetized with xylocaine spray.The mass was then fixed between the index and middle finger, and a 23-gauge needle attached to a 20mL plastic syringe in a syringe holder (CamecoSyringe Pistol Precision Dynamics Corp, Burbank, CA), was inserted into the mass.A full vacuum was applied, and the needle was moved back and forth in the mass with short, quick strokes in slightly different directions.Then the vacuum was released, and the needle was withdrawn.
The aspirated material was expelled instantly onto several slides, and smears were made.Usually, one airdried smear was stained immediately with a quick Giemsa staining to determine the quality of the aspirate.One other smear was fixed in 95% ethanol and stained according to the Papanicolaou method.The remaining smears were air dried and stained according to the May-Gru¨nwald-Giemsa method.
A questionaire regarding the clinical history of the pateint was filled by the parents.

Staining Procedures
May-Grunwald-Giemsa: Air dried smears were stained by May-Grunwald-Giemsa stain (MGG).The air dried smears were stained in diluted MGG solution for 10 minutes, rinsed in pH 6.8 buffer, then stained in the diluted Giemsa solution for 30 minutes and washed and differentiated in pH 6.8 buffer for 15 minutes.
Papanicolaou method: The wet smears were treated with 95% alcohol for one minute, 70% alcohol for two minutes, distilled water for three minutes, then stained with filtered Harri's haematoxylin solution for three minutes, rinsed in water and blued in runing tap water for seven minutes, then rinsed in 90% alcohol for one minute, stained with orange G solution for two minutes, treated with 90% alcohol for one minute, stained with EA 50 solution for two minutes and rinsed in 95% alcohol.The stained slides were then cleared in xylene, mounted in DPX mountant and examined under the microscope.
Cytological diagnosis was stated in 4 categories: benign, malignant, inflammatory, or inadequate material for diagnosis.Confirmation of the cytological diagnosis was done by subsequent clinical follow-up for 6 months.Malignant cases were confirmed later by histopathology and referred to the oncologist.

Data analysis
Data management was done by using the Statistical Package for Social Sciences (SPSS version 16).SPSS was used for analysis and to perform Fisher exact test for statistical significance (p value).The 95% confidence level was used.A p=0.05 was considered statistically significant.
Ethical consent: The study was approved by the ethics board of the Faculty of Medical Laboratory Science, Sudan University for Science and Technology.All the study samples were from peripheral blood taken for routine investigations.Older study patients and their families consented to participation.Further, all specimens were taken as a part of the requirement of diagnosis.

Results
In this lymphadenopathy was investigated by FNAC in 100 children, their age ranging from 2 to 14 years, with a mean age of 7 years.The male female ratio was 1.04:1.00.

Discussion
FNAC of the lymphadenopathy is well accepted as a diagnostic procedure in the adult population, hence, FNAC in the pediatric population is rapidly gaining acceptance as pediatricians build confidence in this diagnostic test (Howell, 2001;Amy et al., 2007).
Fine-needle aspiration cytology is a rapid, simple and accurate diagnostic procedure to differentiate between benign and malignant peripheral lymphadenopathy in children.FNAC can avoid open biopsy in at least 60% of cases.Due to limited resources in Sudan, FNAC is the most frequently used technique for diagnosis of palpable lesions in adults and children.
However, to the best of our knowledge, reports from Sudan detailing the application of FNA cytology to lymph node lesions in the pediatric population are limited.There is only one report from Sudan investigated the cervical lymph node among Sudanese children using FNAC (Jalal and Eltahir, 2012).
In the current study we investigated 100 children presented with enlarged lymph node in different parts of the body.Peripheral lymphadenopathy remains a tremendously common clinical problem in Pediatrics.The causes of peripheral lymphadenopathy are various; the majorities (85% to 87%) are benign self-limiting conditions (Knight et al., 1982).What's more, a lymph proliferative disorder or malignancy often is included in the differential diagnosis.When a malignancy is expected or a lymphadenopathy persists, a morphologic analysis of the lymph node is inevitable (Leon van et al., 2001).
In the present study the majority of cases were identified with reactive lymph nodes (64%).Many studies have reported that reactive lymph node is the commonest condition associated with overall lymph node enlargement (Adesuwa and Egbagbe, 2006;Al-Tawfiq and Raslan, 2012).Reactive Lymph node is a benign and reversible process, which can be caused by many etiologies, most commonly infectious agents (Ciro et al., 2012).Clinical evaluation, serological data, microbiological and molecular tests and imaging techniques are generally important in the diagnosis of reactive lymph nodes determined by infectious diseases but, in some cases; do not assess their origin and nature (Anne et al., 2008).Therefore, one of the limitations in this study we did not perform further investigations to identify the causes of these diagnosed pathological conditions in this study.
Granulomatous lymphadenitis is a common condition associated with lymphadenopathy, which can be caused by Mycobacterium Tuberculosis (Mittal et al., 2011) or by other causes (Harris et al., 2009).In the present study, Granulomatous lymphadentitis represented 26%, which is relatively similar to a study by Annam et al. when investigated 336 consecutive children, aged 1 month to 12 years, the cytomorphologic features observed were reactive lymphadenitis in 58.02% of cases, granulomatous lymphadenitis in 30.55%, suppurative lymphadenitis in 7.10% and malignancies in 5.62% (Annam et al., 2009).
These findings differ from the reported results in a recent study from Sudan when they studied pediatric cervical lymphadenopathy (CLA) in 80 Sudanese children; they found that Hodgkin's lymphoma constituted 5% of the cases of CLA (Jalal and Eltahir, 2012).These variations might be attributed to their sample size which was relatively lower than ours and their restriction to CLA.However, when related the comparison to the site, 7% of lymphoma cases in this study were found with CLA, which is relatively close to the findings of the previous Sudanese study (Jalal and Eltahir, 2012).
Non-Hodgkin's lymphoma (CD30-ve) is the most common immunophenotype in the Sudan, which represented 79%, according to the histological evidences (Ahmed et al., 2011).However, up to now there is no detailed study investigated the immunophenotyping of lymphomas in the Sudan.Most available literature from the Sudan dealt with Burkett's lymphoma.During the period 1962-80 thirty-five cases of Burkett's lymphoma were seen and examined histologically in Khartoum, Sudan (Veress et al., 1976;Yagi et al., 1984).In study from Sudan analyzed Sudan data obtained from a hospital registry for the period May1999 to June 2007, there were 322 children with cancer during this time period with a male: female ratio of 1.6:1.There were 111(35%) cases of lymphomas (Abuidris et al., 2008).Such findings were previously reported (Huang et al., 2011).
According to gender, lymphoma was identified in 70% of males and 30% of females and this ratio was statistically significant p<0.02.The study from Sudan (Jalal and Eltahir, 2012) in this context, found no statistical difference, but similar to our findings, the males were more than females.
Lymphoma was significantly found in the age group above 10years (p<0.001), which similar to the findings of the study from Sudan (Jalal and Eltahir, 2012).Such findings were previously reported by numerous studies (Percy et al., 1999;Clarke and Glaser, 2002;Jaglowski et al., 2009).
In conclusion, non-Hodgkin and Hodgkin lymphoma can be suspected in Sudanese pediatric patients with lymphadenopathy.FNA provides a useful tool in the diagnosis of pediatric patients with peripheral lymphadenopathy.

Figure
Figure 4. Description of the Study Population by Age and Diagnosis

FigureFigure 3 .
Figure 2. Description of FNAC Diagnosis by Site