As highlighted in Chapter 3 and other parts of this book, an accurate diagnosis should precede treatment and provide information about illness course, prognosis, and treatment, as well as facilitating clinical and research communication. Pediatric depressive disorders have been well validated as a diagnostic entity, and a diagnosis of depression in childhood has clear prognostic implications.20 Given the complex relationship between depression and physical disease, a careful assessment is critical. The clinician must appreciate how physical disease and its treatment impact on mood, and remain alert to how mood and mood disorder may impact on chronic physical illness.

The differential diagnosis of depressive syndromes in children with chronic physical illness is broad and includes, but is not limited to, primary mood disorders (e.g., major depressive disorder, dysthymic disorder, bipolar disorder), transient reactions to stressors (e.g., adjustment disorders, bereavement), and mood disorders secondary to a general medical condition or its treatment (e.g., nutritional deficiency, left-sided stroke, tacrolimus, or steroid immunosuppression) (see also Table 1.4). Specific diagnostic criteria for each have been described in Chapters 1, 3, and elsewhere.21,22 Depressive disorders are also frequently comorbid with other psychiatric disorders in physically ill youth, including anxiety disorders and posttraumatic stress disorder. In circumstances where there is considerable impairment, yet uncertainty about the specific diagnosis remains, it may be possible to identify circumscribed symptoms that are amenable to intervention.

Clinicians face numerous challenges in the evaluation and diagnosis of depression in chronically ill children. An integrative approach is recommended, with particular emphasis on the evaluation of changes in functioning from baseline and across domains. Consequently, clinicians working with chronically ill youth need to gather information from multiple sources and coordinate care with parents, other medical professionals, family, social agencies, schools, and relevant community systems. The taxing consequences of the child’s chronic physical illness for the child and family should be assessed and relevant findings incorporated into treatment planning. Attention should be paid to peer interactions and developmental tasks that are disrupted by the illness, its timing, or its effects on physical appearance, sexual identity and development, and functional status. Individual, developmental, family, and cultural health beliefs and the quality of communication between the family, patient, and medical care providers should be assessed and included as relevant to the biopsychosocial formulation and as potential targets for intervention. Possible medicolegal issues and the role of health-care systems should also be explored. The possibility that the child’s depressive symptoms may be explained, wholly or in part, by the comorbid physical disease should always be considered and the current and past medical history should be carefully reviewed. Current and recently prescribed medications should be determined, including the use of contraceptives, vitamins, dietary supplements, and herbal remedies. The clinician should consult the package insert, Internet resources, the pharmacy service, and the Medical Letter regarding potential psychiatric effects of current medications. It should be always kept in mind the possibility that a female patient may be pregnant. The possibility that a female patient may be pregnant should always be kept in mind.

Much has been written about the challenges associated with diagnosing depressive disorders in the physically ill, with both under- and overdiagnosis generating concern. Underrecognition reduces the number of youth capable of experiencing symptomatic relief and functional improvement, whereas overdiagnosis may be associated with the risk of stigmatizing a particular child or exposing him or her to needless or overly aggressive treatment. The risk of misattributing symptoms of the chronic physical disease (e.g., fatigue or poor sleep or appetite) to a mood disorder has been a topic of much discussion. Attributing a symptom such as fatigue to either the physical disease or to depression is highly subjective and thus notoriously unreliable. Similarly, dysphoria in the context of chronic physical illness must also be assessed, and a sympathetic adult can easily “explain away” associated emotional distress as situational and an adjustment to the existing physical health problem.

Although differentiating the consequences of traditional physical disease from depression is challenging, the existing social context and the stigma associated with a diagnosis of mental disorder and psychiatric treatment appear to mitigate the likelihood of reckless overdiagnosis of depression in chronically ill youth. Stigma can be a powerful and often subliminal motivation to consider subjective and somatic symptoms of depression as only a consequence of the physical disease and thus “nothing to be ashamed of.” Well-meaning professionals may also wish to spare any additional “insult” to an already suffering child and family. It can thus be tempting for patients, families, and professionals to dismiss signs and symptoms of depression as a part of a “normal” or “justifiable” response to the underlying chronic illness. Biases in favor of or against the diagnosis of psychiatric disorder in the physically ill child have real consequences. Inadvertently creating a higher standard to diagnose depression in the physically ill results in underdiagnosis, and it places patients at further risk of physical and emotional decompensation owing to lack of treatment.

Because existing evidence suggests that most depressed children and adolescents are either unrecognized or inadequately treated, we recommend an inclusive approach to the diagnosis that considers all symptoms of depression elicited during examination as relevant regardless of whether physical illness could be responsible or not.23 This approach requires clinicians to address all potential sources of the patient’s subjective distress and impairment, and to initiate treatment based on a thoughtful evaluation of the risks and benefits in collaboration with the patient and family. Clinicians should carry out necessary laboratory investigations and request subspecialty consultation as guided by findings in the history and physical examination. Careful review of medications, with close attention to temporal relationships between psychiatric symptoms and the timing of medication initiation, discontinuation, and dosing change can be an invaluable part of the assessment. In our experience, by considering all symptoms of depression noted on examination to be relevant to the diagnosis of depression, the inclusive approach increases the sensitivity of clinicians to depression in the physically ill and is likely to be more reliable than one relying on the subjective judgment of clinicians in determining whether a particular symptom is “physical” or “mental.”

As described in earlier chapters, clinical research has documented the efficacy of several interventions for pediatric depression,24 including psychotherapeutic treatments such as cognitive behavior therapy (CBT) (see Chapter 8) and interpersonal psychotherapy (IPT) (see Chapter 9), and pharmacologic treatment with antidepressants, most notably SSRIs25,26 (see Chapter 6). Despite a lack of large RCTs addressing the treatment of depression in physically ill youth, there is no evidence that depressed youth with comorbid physical illness are less likely to respond to proven treatments than their physically healthy counterparts. It is somewhat reassuring that depressed adults with chronic physical illness appear to respond to treatment at levels comparable with those of healthy adults.27 Consequently, active treatment consistent with the safe and effective management of depression in physically healthy children should be pursued in youth struggling with comorbid physical disease.